In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was inves...In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy （SEM） results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter （DSC） test and X-ray diffraction （XRD） characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.展开更多
Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a ...Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a compatibilizer.The synergistic effects of the two additives on the mechanical,thermal,and morphological properties of the PLA/PBAT blend films were investigated.The influence of TEC content on the plasticized PLA films and the effect of TDI’s presence on the PLA/PBAT blend films were also studied by comparing them with neat PLA.The results showed a pronounced increase in elongation at break of the plasticized PLA films with increasing TEC levels,but a slight reduction in thermal stability.Also,the addition of TEC and TDI to the blend system not only synergistically enhanced the tensile properties and tensile-impact strength of the PLA/PBAT blends,but also affected their crystallinity and cold crystallization rate,a result of the improvement of interfacial interaction between PLA and PBAT,including the enhancement of their chain mobility.The synergy of the plasticization and compatibilization processes led to the improvement of tensile properties,tensile-impact strength,and compatibility of the blends,accelerating cold crystallization without affecting crystallization.展开更多
Polylactide （PLA） films blended with 10 wt% poly（butylene adipate-co-terephthalate） （PBAT） were prepared by using a twin screw extruder in the presence of the nucleating agent of titanium dioxide （TiO2） and th...Polylactide （PLA） films blended with 10 wt% poly（butylene adipate-co-terephthalate） （PBAT） were prepared by using a twin screw extruder in the presence of the nucleating agent of titanium dioxide （TiO2） and the compatibilizers of toluene diisocyanate （TDI） and PLA-grafted-maleic anhydride （PLA-g-MA）. The synergistic effect of the nucleation and compatibilization on the properties and crystallization behavior of the PLA/PBAT （PLB） films was explored. The results showed that the addition of TiO2 significantly enhanced the tensile strength and the impact tensile resistance of the PLB films while slightly decreased its thermal stability. In addition, the compatibilizers of TDI and PLA-g-MA in the system not only affected the crystallinity and cold crystallization process of the PLB films, but also increased the mechanical properties of them due to the improvement of the interracial interaction between PLA and PBAT revealed by the morphological measurement. The synergistic effects of the nucleating agent and the compatibilizer afforded the blend films with increased tensile strength and impact tensile toughness, improved cold crystallization property and Xc.展开更多
The toughened poly(L-lactic acid)/poly(butylene succinate-butylene terephthalate)(PLLA/PBST) blend with enhanced melt strength and excellent low temperature toughness and strength was prepared by melt compounding thro...The toughened poly(L-lactic acid)/poly(butylene succinate-butylene terephthalate)(PLLA/PBST) blend with enhanced melt strength and excellent low temperature toughness and strength was prepared by melt compounding through in situ compatibilization reaction in presence of multifunctional epoxy compound(ADR).The PLLA/PBST blend was an immiscible system,and the compatibility of the PLLA/PBST blend was improved after adding ADR.FTIR and GPC curves confirmed the formation of the PLLA-g-PBST copolymer,which improved the interfacial bonding of the blend and therefore the PLLA/PBST/ADR blend showed excellent melt strength and mechanical properties.For the PLLA/PBST/ADR blend with 70/30 PLLA/PBST content,the complex viscosity increased significantly with increasing ADR content.Moreover,the tensile strength,elongation at break and impact strength all increased obviously with increasing the ADR content.The elongation at break of the blend reached the maximum value of 392.7%,which was 93.2 times that of neat PLLA.And the impact strength of the blend reached the maximum value of 74.7 k J/m~2,which was 21.3 times that of neat PLLA.Interestingly,the PLLA/PBST/ADR blend exhibited excellent lowtemperature toughness and strength.At –20 ℃,the elongation at break of the PLLA/PBST/ADR blend was as high as 93.2%,and the impact strength reached 18.8 k J/m~2.Meanwhile,the tensile strength of the blend at low temperature was also high(64.7 MPa),which was beneficial to the application of PLA in the low temperature field.In addition,the PLLA/PBST/ADR blend maintaind good biodegradability,which was of great significance to the wide application of PLLA.展开更多
A side-chain liquid crystalline ionomer（SLCI） was synthesized by grafting copolymerization of 4-（4-ethoxybenzoyloxy）-4＇-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blend...A side-chain liquid crystalline ionomer（SLCI） was synthesized by grafting copolymerization of 4-（4-ethoxybenzoyloxy）-4＇-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blended with polypropylene（PP） and polybutylene terephthalate（PBT） by melt mixing. The thermal behavior, liquid crystalline properties, morphological structure, and mechanical properties of the blends were investigated by differential scanning calorimetry（DSC）, polarizing optical microscopy（POM）, scanning electron microscopy（SEM）, and tensile measurement. When a proper amount of SLCI was added, fine configurations were formed in the PBT/PP/SLCI blend system, and the mechanical properties were improved due to improved adhesion at the interface. When excess SLCI was added, an inhomogeneous structure resulted, which caused the mechanical properties to deteriorate.展开更多
Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly（lactic acid）（PLA） and poly（propylene carbonate）（PPC）. By virtue of their similar chemical structures, in situ c...Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly（lactic acid）（PLA） and poly（propylene carbonate）（PPC）. By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide（DCP） between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.展开更多
This paper investigated the influences of butadiene rubber (BR) and dicumyl peroxide (DCP) on thermal and rheological behaviour, morphology and mechanical properties of PS/LLDPE/SBS blend. Addition of DCP alone was fo...This paper investigated the influences of butadiene rubber (BR) and dicumyl peroxide (DCP) on thermal and rheological behaviour, morphology and mechanical properties of PS/LLDPE/SBS blend. Addition of DCP alone was found to decrease the mechanical properties of PS/LLDPE/SBS blend due to the decomposition of PS. When BR was added together with DCP, it is found that the co-crosslinking of BR, SBS and PE takes place, and the decomposition of PS is reduced simultaneously because of the consumption of the free radicals in the crosslinking process. Synergism was thus realised which resulted in the improvement of the ductility of blend.展开更多
The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematic...The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematically investigated. Scanning electron microscopy （SEM） and differential scanning calorimetry （DSC） were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam （ADCB） method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.展开更多
The effects of styrene-ethylene/propylene (SEP) diblock copolymer on the morphology and mechanical propertiesof polypropylene/polystyrene (PP/PS) blends were investigated. The results showed that SEP diblock copolymer...The effects of styrene-ethylene/propylene (SEP) diblock copolymer on the morphology and mechanical propertiesof polypropylene/polystyrene (PP/PS) blends were investigated. The results showed that SEP diblock copolymer, acting as acompatibilizer in PP/PS immiscible blends, can diminish the coalescence of the dispersed particles, reduce their averageparticle size, change their phase morphologies significantly, and increase the mechanical properties. It was found that SEP has better compatibilization effects on the PP/PS (20/80) blends.展开更多
Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and ...Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.展开更多
Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importan...Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.展开更多
In situ, compatibilization of low density polyethylene (LDPE) (30%) and nylon-6 (70%) blends through one-step reactive extrusion using t-BuOOH as an initiator and low molecular weight interfacial agents as compatibili...In situ, compatibilization of low density polyethylene (LDPE) (30%) and nylon-6 (70%) blends through one-step reactive extrusion using t-BuOOH as an initiator and low molecular weight interfacial agents as compatibilizers was studied. The compatibilizer contained a long chain hydrocarbon, double bond and two polar functional groups which was capable of reacting with both LDPE and nylon-6 in the presence of initiator to form a copolymer at the interface of the two polymer phases. The extruded blends exhibited significant enhancement in their compatibility based on morphological, thermal analysis and mechanical studies. The effect of the hydrocarbon chain length and structure of the functional group of the compatibilizer was also examined. It was found that blends prepared by using the compatibilizer containing longer hydrocarbon chain and amide group had better mechanical properties.展开更多
Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interfac...Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interface anchoring,and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy,while their low affinity to bulk components is a drawback.In this study,an interfacial atom transfer radical polymerization(ATRP)technique was employed to grow polystyrene(PS)and poly(2-hydroxyethyl methacrylate)(PHEMA)simultaneously on different hemispheres of Br-functionalized SiO_(2) nanoparticles to stabilize a Pickering emulsion,whereby a brush-type Janus nanoparticle(SiO_(2)@JNP)was developed.The polymer brushes were well-characterized,and the Janus feature was validated by transmission electron microscope(TEM)observation of the sole hemisphere grafting of SiO_(2)-PS as a control sample.SiO_(2)@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate)(PMMA)immiscible blend,and the droplet-matrix morphology was significantly refined.The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO_(2)@JNP optimized~0.9 wt%,with the tensile strength,elongation at break and impact strength increased by 17.7%,26.6%and 19.6%,respectively.This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion.展开更多
High-entropy polymer blends composed of polypropylene(PP),polystyrene(PS),polyamide 6(PA6),poly(lactic acid)(PLA),and styrene-ethylene-butylene-styrene(SEBS)were successfully fabricated using maleic anhydride-grafted ...High-entropy polymer blends composed of polypropylene(PP),polystyrene(PS),polyamide 6(PA6),poly(lactic acid)(PLA),and styrene-ethylene-butylene-styrene(SEBS)were successfully fabricated using maleic anhydride-grafted SEBS(SEBS-g-MAH)as a compatibilizer.Dynamic mechanical analysis(DMA),differential scanning calorimetry(DSC),scanning electron microscopy(SEM),and mechanical testing demonstrated that SEBS-g-MAH significantly enhanced the compatibility between the polar(PA6,PLA)and nonpolar(PP,PS,SEBS)components.The compatibilizer effectively refined the microstructure,substantially reduced the domain sizes,and blurred the phase boundaries,indicating enhanced interfacial interactions among all the components.The optimal compatibilizer content(15 wt%)notably increased tensile ductility(elongation at break from 5.0%to 23.7%)while maintaining balanced crystallization behavior,despite slightly decreasing modulus.This work not only demonstrates the broad applicability of high-entropy polymer blends as a sustainable strategy for converting complex,unsorted plastic waste into high-performance value-added materials that significantly contribute to plastic upcycling efforts,but also highlights intriguing physical phenomena emerging from such complex polymer systems.展开更多
Here,the effects of compatibilization and clay nanoparticles on the gas permeability of nanocomposites of poly-lactic acid(PLA)/thermoplastic starch(TPS)/nanoclay were discussed.TPS and compatibilized PLA/TPS were tai...Here,the effects of compatibilization and clay nanoparticles on the gas permeability of nanocomposites of poly-lactic acid(PLA)/thermoplastic starch(TPS)/nanoclay were discussed.TPS and compatibilized PLA/TPS were tailored in the first step.The starch with D-sorbitol as a plasticizer was mingled through the internal mixer.Afterward,the maleination method was utilized on PLA to ameliorate the compatibilization of PLA and TPS.In this regard,maleic anhydrate(MA)has been grafted on PLA in the presence of L101 as a peroxide initiator via melt mixing to obtain PLA-g-MA.The optimum content of PLAg-MA was about 4 phr,confirmed by DMTA and SEM.Noteworthy,the presence of PLA-g-MA has moderately improved the oxygen barrier.Then,the nanocomposites of PLA and TPS containing 1%of Cloisite-30B as well as the optimum compatibilizer(4phr),were produced by melt mixing in the masterbatch module leading to the formation of an extraordinary well-dispersed structure according to XRD patterns.The mixing order controlled the localization of nanosheets.It was concluded that the inclusion of 1%nanoclay in the PLA phase reduces the oxygen permeability by 55%compared to the pristine blend due to the tortuosity effect of nanosheets that are appropriately dispersed in the matrix.展开更多
The effect of maleic anhydride grafted styrene-ethylene- buty-lene-styrene block copolymer （SEBS-g-MAH） and in-situ grafting MAH on mechanical, dynamic mechanical properties of wood flour/recycled plastic blends com...The effect of maleic anhydride grafted styrene-ethylene- buty-lene-styrene block copolymer （SEBS-g-MAH） and in-situ grafting MAH on mechanical, dynamic mechanical properties of wood flour/recycled plastic blends composites was investigated. Recycled plastic polypro-pylene （PP）, high-density polyethylene （HDPE） and polystyrene （PS）, were mixed with wood flour in a high speed blender and then extruded by a twin/single screw tandem extruder system to form wood flour/recycled plastic blends composites. Results show that the impact properties of the composites were improved more significantly by using SEBS-g-MAH compatibilizer than by using the mixtures of MAH and DCP via reactive blending in situ. However, contrary results were ob-served on the tensile and flexural properties of the corresponding com-posites. In General, the mechanical properties of composites made from recycled plastic blends were inferior to those made from virgin plastic blends, especially in elongation break. The morphological study verified that the interfacial adhesion or the compatibility of plastic blends with wood flour was improved by adding SEBS-g-MAH or in-situ grafting MAH. A better interfacial bonding between PP, HDPE, PS and wood flour was obtained by in-situ grafting MAH than the addition of SEBS-g-MAH. In-situ grafting MAH can be considered as a potential way of increasing the interfacial compatibility between plastic blends and wood flour. The storage modulus and damping factor of composites were also characterized through dynamic mechanical analysis （DMA）.展开更多
Ethylene/propylene-random-copolymer （PPR）/clay nanocomposites were prepared by two-stage melt blending. Four types of compatibilizers, including an ethylene-octene copolymer grafted maleic anhydride （POE-g-MA） and...Ethylene/propylene-random-copolymer （PPR）/clay nanocomposites were prepared by two-stage melt blending. Four types of compatibilizers, including an ethylene-octene copolymer grafted maleic anhydride （POE-g-MA） and three maleic-anhydride-grafted polypropylenes （PP-g-MA） with different melt flow indexes （MFI）, were used to improve the dispersion of organic clay in matrix. On the other hand, the effects of organic montmorillonite （OMMT） content on the nanocomposite structure in terms of clay dispersion in PPR matrix, thermal behavior and tensile properties were also studied. The X-ray diffraction （XRD） and transmission electron microscopy （TEM） results show that the organic clay layers are mainly intercalated and partially exfoliated in the nanocomposites. Moreover, a PP-g-MA compatibilizer （compatibilizer B） having high MFI can greatly increase the interlayer spacing of the clay as compared with other compatibilizers. With the introduction of compatibilizer D （POE-g-MA）, most of the clays are dispersed into the POE phase, and the shape of the dispersed OMMT appears elliptic, which differs from the strip of PP-g-MA. Compared with virgin PPR, the Young＇s modulus of the nanocomposite evidently increases when a compatibilizer C （PP-g-MA） with medium MFI is used. For the nanocomposites with compatibilizer B and C, their crystallinities （Xc） increase as compared with that of the virgin PPR. Furthermore, the increase of OMMT loadings presents little effect on the melt temperature （Tc） of the PPR/OMMT nanocomposites, and slight effect on their crystallization temperature （Tc）. Only compatibilizer B can lead to a marked increases in crystallinity and Tc of the nanocomposite when the OMMT content is 2 wt%.展开更多
In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly...In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.展开更多
One-step reaction compatibilized microfibrillar reinforced iPP/PET blends （CMRB） were successfully prepared through a ＂slit extrusion-hot stretching-quenching＂ process. Crystallization behavior and morphology of C...One-step reaction compatibilized microfibrillar reinforced iPP/PET blends （CMRB） were successfully prepared through a ＂slit extrusion-hot stretching-quenching＂ process. Crystallization behavior and morphology of CMRB were systematically investigated. Scanning electronic microscopy （SEM） observations showed blurry interface of compatibilized common blend （CCB）. The crystallization behavior of neat iPP, CCB, microfibrillar reinforced iPP/PET blend （MRB） and CMRB was investigated by differential scanning calorimetry （DSC） and polarized optical microscopy （POM）. The increase of crystallization temperature and crystallization rate during nonisothermal crystallization process indicated both PET particles and mierofibrils could serve as nucleating agents and PET microfibrils exhibited higher heterogeneous nucleation ability, which were also vividly revealed by results of POM. Compared with MRB sample, CMRB sample has lower crystallization temperature due to existence of PET microfibrils with smaller aspect ratio and wider distribution. In addition, since in situ compatibilizer tends to stay in the interphase, it could also hinder the diffusion ofiPP molecules to the surface of PET phase, leading to decrease of crystallization rate. Two-dimensional wide-angle X-ray diffi：action （2D-WAXD） was preformed to characterize the crystalline structure of the samples by injection molding, and it was found that well-developed PET microfibrils contained in MRB sample promoted formation of t-phase of/PP.展开更多
The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional ep...The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.展开更多
文摘In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy （SEM） results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter （DSC） test and X-ray diffraction （XRD） characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.
基金financially supported by Development and Promotion of Science and Technology Talents (DPST) (No. 013/2559)
文摘Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a compatibilizer.The synergistic effects of the two additives on the mechanical,thermal,and morphological properties of the PLA/PBAT blend films were investigated.The influence of TEC content on the plasticized PLA films and the effect of TDI’s presence on the PLA/PBAT blend films were also studied by comparing them with neat PLA.The results showed a pronounced increase in elongation at break of the plasticized PLA films with increasing TEC levels,but a slight reduction in thermal stability.Also,the addition of TEC and TDI to the blend system not only synergistically enhanced the tensile properties and tensile-impact strength of the PLA/PBAT blends,but also affected their crystallinity and cold crystallization rate,a result of the improvement of interfacial interaction between PLA and PBAT,including the enhancement of their chain mobility.The synergy of the plasticization and compatibilization processes led to the improvement of tensile properties,tensile-impact strength,and compatibility of the blends,accelerating cold crystallization without affecting crystallization.
基金financially supported by the Prince of Songkla University(No.SCI570376S)the Development and Promotion of Science and Technology Talents project(DPST)
文摘Polylactide （PLA） films blended with 10 wt% poly（butylene adipate-co-terephthalate） （PBAT） were prepared by using a twin screw extruder in the presence of the nucleating agent of titanium dioxide （TiO2） and the compatibilizers of toluene diisocyanate （TDI） and PLA-grafted-maleic anhydride （PLA-g-MA）. The synergistic effect of the nucleation and compatibilization on the properties and crystallization behavior of the PLA/PBAT （PLB） films was explored. The results showed that the addition of TiO2 significantly enhanced the tensile strength and the impact tensile resistance of the PLB films while slightly decreased its thermal stability. In addition, the compatibilizers of TDI and PLA-g-MA in the system not only affected the crystallinity and cold crystallization process of the PLB films, but also increased the mechanical properties of them due to the improvement of the interracial interaction between PLA and PBAT revealed by the morphological measurement. The synergistic effects of the nucleating agent and the compatibilizer afforded the blend films with increased tensile strength and impact tensile toughness, improved cold crystallization property and Xc.
基金financially supported by the Science and Technology Development Plan of Jilin Province (No. 20210203199SF)。
文摘The toughened poly(L-lactic acid)/poly(butylene succinate-butylene terephthalate)(PLLA/PBST) blend with enhanced melt strength and excellent low temperature toughness and strength was prepared by melt compounding through in situ compatibilization reaction in presence of multifunctional epoxy compound(ADR).The PLLA/PBST blend was an immiscible system,and the compatibility of the PLLA/PBST blend was improved after adding ADR.FTIR and GPC curves confirmed the formation of the PLLA-g-PBST copolymer,which improved the interfacial bonding of the blend and therefore the PLLA/PBST/ADR blend showed excellent melt strength and mechanical properties.For the PLLA/PBST/ADR blend with 70/30 PLLA/PBST content,the complex viscosity increased significantly with increasing ADR content.Moreover,the tensile strength,elongation at break and impact strength all increased obviously with increasing the ADR content.The elongation at break of the blend reached the maximum value of 392.7%,which was 93.2 times that of neat PLLA.And the impact strength of the blend reached the maximum value of 74.7 k J/m~2,which was 21.3 times that of neat PLLA.Interestingly,the PLLA/PBST/ADR blend exhibited excellent lowtemperature toughness and strength.At –20 ℃,the elongation at break of the PLLA/PBST/ADR blend was as high as 93.2%,and the impact strength reached 18.8 k J/m~2.Meanwhile,the tensile strength of the blend at low temperature was also high(64.7 MPa),which was beneficial to the application of PLA in the low temperature field.In addition,the PLLA/PBST/ADR blend maintaind good biodegradability,which was of great significance to the wide application of PLLA.
基金Supported by the National Natural Science Foundation of China(No50673105)
文摘A side-chain liquid crystalline ionomer（SLCI） was synthesized by grafting copolymerization of 4-（4-ethoxybenzoyloxy）-4＇-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blended with polypropylene（PP） and polybutylene terephthalate（PBT） by melt mixing. The thermal behavior, liquid crystalline properties, morphological structure, and mechanical properties of the blends were investigated by differential scanning calorimetry（DSC）, polarizing optical microscopy（POM）, scanning electron microscopy（SEM）, and tensile measurement. When a proper amount of SLCI was added, fine configurations were formed in the PBT/PP/SLCI blend system, and the mechanical properties were improved due to improved adhesion at the interface. When excess SLCI was added, an inhomogeneous structure resulted, which caused the mechanical properties to deteriorate.
基金financially supported by the National Natural Science Foundation of China(No.51503117)the Innovation Foundation for Graduate Students of Shandong University of Science and Technology,China(No.SDKDYC170334)
文摘Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly（lactic acid）（PLA） and poly（propylene carbonate）（PPC）. By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide（DCP） between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.
基金The project is supported by the National Natural Science Foundation of China.
文摘This paper investigated the influences of butadiene rubber (BR) and dicumyl peroxide (DCP) on thermal and rheological behaviour, morphology and mechanical properties of PS/LLDPE/SBS blend. Addition of DCP alone was found to decrease the mechanical properties of PS/LLDPE/SBS blend due to the decomposition of PS. When BR was added together with DCP, it is found that the co-crosslinking of BR, SBS and PE takes place, and the decomposition of PS is reduced simultaneously because of the consumption of the free radicals in the crosslinking process. Synergism was thus realised which resulted in the improvement of the ductility of blend.
基金financially supported by the National Natural Science Foundation of China(No.21004069)
文摘The influences of hyperbranched polyethylenimine （hPEI）, which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate （PC） and amorphous polyamide （aPA） were systematically investigated. Scanning electron microscopy （SEM） and differential scanning calorimetry （DSC） were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam （ADCB） method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.
基金This research was supported by the Natural Science Foundation of Guangdong Province (No. 960220).
文摘The effects of styrene-ethylene/propylene (SEP) diblock copolymer on the morphology and mechanical propertiesof polypropylene/polystyrene (PP/PS) blends were investigated. The results showed that SEP diblock copolymer, acting as acompatibilizer in PP/PS immiscible blends, can diminish the coalescence of the dispersed particles, reduce their averageparticle size, change their phase morphologies significantly, and increase the mechanical properties. It was found that SEP has better compatibilization effects on the PP/PS (20/80) blends.
基金supported by the National Natural Science Foundation of China(No.51525301).
文摘Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.
文摘Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.
文摘In situ, compatibilization of low density polyethylene (LDPE) (30%) and nylon-6 (70%) blends through one-step reactive extrusion using t-BuOOH as an initiator and low molecular weight interfacial agents as compatibilizers was studied. The compatibilizer contained a long chain hydrocarbon, double bond and two polar functional groups which was capable of reacting with both LDPE and nylon-6 in the presence of initiator to form a copolymer at the interface of the two polymer phases. The extruded blends exhibited significant enhancement in their compatibility based on morphological, thermal analysis and mechanical studies. The effect of the hydrocarbon chain length and structure of the functional group of the compatibilizer was also examined. It was found that blends prepared by using the compatibilizer containing longer hydrocarbon chain and amide group had better mechanical properties.
基金financially supported by the National Natural Science Foundation of China(Nos.22172028,21903015,and 22403017)Natural Science Foundation of Fujian Province of China(No.2022J05041)。
文摘Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interface anchoring,and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy,while their low affinity to bulk components is a drawback.In this study,an interfacial atom transfer radical polymerization(ATRP)technique was employed to grow polystyrene(PS)and poly(2-hydroxyethyl methacrylate)(PHEMA)simultaneously on different hemispheres of Br-functionalized SiO_(2) nanoparticles to stabilize a Pickering emulsion,whereby a brush-type Janus nanoparticle(SiO_(2)@JNP)was developed.The polymer brushes were well-characterized,and the Janus feature was validated by transmission electron microscope(TEM)observation of the sole hemisphere grafting of SiO_(2)-PS as a control sample.SiO_(2)@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate)(PMMA)immiscible blend,and the droplet-matrix morphology was significantly refined.The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO_(2)@JNP optimized~0.9 wt%,with the tensile strength,elongation at break and impact strength increased by 17.7%,26.6%and 19.6%,respectively.This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion.
基金supported by the National Natural Science Foundation of China(No.52173017)the Project of Introducing Urgently Needed and Scarce Talents in Key Supported Regions of Shandong Province in 2024.
文摘High-entropy polymer blends composed of polypropylene(PP),polystyrene(PS),polyamide 6(PA6),poly(lactic acid)(PLA),and styrene-ethylene-butylene-styrene(SEBS)were successfully fabricated using maleic anhydride-grafted SEBS(SEBS-g-MAH)as a compatibilizer.Dynamic mechanical analysis(DMA),differential scanning calorimetry(DSC),scanning electron microscopy(SEM),and mechanical testing demonstrated that SEBS-g-MAH significantly enhanced the compatibility between the polar(PA6,PLA)and nonpolar(PP,PS,SEBS)components.The compatibilizer effectively refined the microstructure,substantially reduced the domain sizes,and blurred the phase boundaries,indicating enhanced interfacial interactions among all the components.The optimal compatibilizer content(15 wt%)notably increased tensile ductility(elongation at break from 5.0%to 23.7%)while maintaining balanced crystallization behavior,despite slightly decreasing modulus.This work not only demonstrates the broad applicability of high-entropy polymer blends as a sustainable strategy for converting complex,unsorted plastic waste into high-performance value-added materials that significantly contribute to plastic upcycling efforts,but also highlights intriguing physical phenomena emerging from such complex polymer systems.
基金supported by the National Natural Science Foundation of China[Grant No.51703083]the Project“Fibre materials and products for emergency support and public safety”from Jiangsu New Horizon Advanced Functional Fibre Innovation Center Co.Ltd.[Grant No.2020-fx020026]。
文摘Here,the effects of compatibilization and clay nanoparticles on the gas permeability of nanocomposites of poly-lactic acid(PLA)/thermoplastic starch(TPS)/nanoclay were discussed.TPS and compatibilized PLA/TPS were tailored in the first step.The starch with D-sorbitol as a plasticizer was mingled through the internal mixer.Afterward,the maleination method was utilized on PLA to ameliorate the compatibilization of PLA and TPS.In this regard,maleic anhydrate(MA)has been grafted on PLA in the presence of L101 as a peroxide initiator via melt mixing to obtain PLA-g-MA.The optimum content of PLAg-MA was about 4 phr,confirmed by DMTA and SEM.Noteworthy,the presence of PLA-g-MA has moderately improved the oxygen barrier.Then,the nanocomposites of PLA and TPS containing 1%of Cloisite-30B as well as the optimum compatibilizer(4phr),were produced by melt mixing in the masterbatch module leading to the formation of an extraordinary well-dispersed structure according to XRD patterns.The mixing order controlled the localization of nanosheets.It was concluded that the inclusion of 1%nanoclay in the PLA phase reduces the oxygen permeability by 55%compared to the pristine blend due to the tortuosity effect of nanosheets that are appropriately dispersed in the matrix.
基金supported by the National High Technology Research and Development Program of China(2010AA101703)the Natural Science Foundation of Heilongjiang Province of China (C200950)the Fundamental Research Fundsfor the Central Universities (DL09BB38)
文摘The effect of maleic anhydride grafted styrene-ethylene- buty-lene-styrene block copolymer （SEBS-g-MAH） and in-situ grafting MAH on mechanical, dynamic mechanical properties of wood flour/recycled plastic blends composites was investigated. Recycled plastic polypro-pylene （PP）, high-density polyethylene （HDPE） and polystyrene （PS）, were mixed with wood flour in a high speed blender and then extruded by a twin/single screw tandem extruder system to form wood flour/recycled plastic blends composites. Results show that the impact properties of the composites were improved more significantly by using SEBS-g-MAH compatibilizer than by using the mixtures of MAH and DCP via reactive blending in situ. However, contrary results were ob-served on the tensile and flexural properties of the corresponding com-posites. In General, the mechanical properties of composites made from recycled plastic blends were inferior to those made from virgin plastic blends, especially in elongation break. The morphological study verified that the interfacial adhesion or the compatibility of plastic blends with wood flour was improved by adding SEBS-g-MAH or in-situ grafting MAH. A better interfacial bonding between PP, HDPE, PS and wood flour was obtained by in-situ grafting MAH than the addition of SEBS-g-MAH. In-situ grafting MAH can be considered as a potential way of increasing the interfacial compatibility between plastic blends and wood flour. The storage modulus and damping factor of composites were also characterized through dynamic mechanical analysis （DMA）.
基金supported by the National Basic Research Program of China(No.2005CB623800)Joint Research Fund for Overseas Chinese Young Scholars(No.50728302)the Program for Zhejiang Provincial Innovative Research Team (No.2009R50004)
文摘Ethylene/propylene-random-copolymer （PPR）/clay nanocomposites were prepared by two-stage melt blending. Four types of compatibilizers, including an ethylene-octene copolymer grafted maleic anhydride （POE-g-MA） and three maleic-anhydride-grafted polypropylenes （PP-g-MA） with different melt flow indexes （MFI）, were used to improve the dispersion of organic clay in matrix. On the other hand, the effects of organic montmorillonite （OMMT） content on the nanocomposite structure in terms of clay dispersion in PPR matrix, thermal behavior and tensile properties were also studied. The X-ray diffraction （XRD） and transmission electron microscopy （TEM） results show that the organic clay layers are mainly intercalated and partially exfoliated in the nanocomposites. Moreover, a PP-g-MA compatibilizer （compatibilizer B） having high MFI can greatly increase the interlayer spacing of the clay as compared with other compatibilizers. With the introduction of compatibilizer D （POE-g-MA）, most of the clays are dispersed into the POE phase, and the shape of the dispersed OMMT appears elliptic, which differs from the strip of PP-g-MA. Compared with virgin PPR, the Young＇s modulus of the nanocomposite evidently increases when a compatibilizer C （PP-g-MA） with medium MFI is used. For the nanocomposites with compatibilizer B and C, their crystallinities （Xc） increase as compared with that of the virgin PPR. Furthermore, the increase of OMMT loadings presents little effect on the melt temperature （Tc） of the PPR/OMMT nanocomposites, and slight effect on their crystallization temperature （Tc）. Only compatibilizer B can lead to a marked increases in crystallinity and Tc of the nanocomposite when the OMMT content is 2 wt%.
文摘In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.
基金financially supported by National Natural Science Foundation of China(No.20776087)National Programs for High Technology Research and Development of China(No.2008AA03Z510)
文摘One-step reaction compatibilized microfibrillar reinforced iPP/PET blends （CMRB） were successfully prepared through a ＂slit extrusion-hot stretching-quenching＂ process. Crystallization behavior and morphology of CMRB were systematically investigated. Scanning electronic microscopy （SEM） observations showed blurry interface of compatibilized common blend （CCB）. The crystallization behavior of neat iPP, CCB, microfibrillar reinforced iPP/PET blend （MRB） and CMRB was investigated by differential scanning calorimetry （DSC） and polarized optical microscopy （POM）. The increase of crystallization temperature and crystallization rate during nonisothermal crystallization process indicated both PET particles and mierofibrils could serve as nucleating agents and PET microfibrils exhibited higher heterogeneous nucleation ability, which were also vividly revealed by results of POM. Compared with MRB sample, CMRB sample has lower crystallization temperature due to existence of PET microfibrils with smaller aspect ratio and wider distribution. In addition, since in situ compatibilizer tends to stay in the interphase, it could also hinder the diffusion ofiPP molecules to the surface of PET phase, leading to decrease of crystallization rate. Two-dimensional wide-angle X-ray diffi：action （2D-WAXD） was preformed to characterize the crystalline structure of the samples by injection molding, and it was found that well-developed PET microfibrils contained in MRB sample promoted formation of t-phase of/PP.
基金This work was financially supported by the National Natural Science Foundation of China(No.51803224).
文摘The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.
