Recently, hyperbranched polymers(HBPs), which differ significantly in structure and properties from linear, cross-linked and branched analogs, have become increasingly important. HBP have a spatial unloaded core and a...Recently, hyperbranched polymers(HBPs), which differ significantly in structure and properties from linear, cross-linked and branched analogs, have become increasingly important. HBP have a spatial unloaded core and a shell of branched monomer units(dendrons), in which functional groups are predominantly located in the surface layer. The size of macromolecules ranges from 2 nm to 100 nm. Currently, there are a fairly large number of publications in the literature devoted to the modification of hyperbranched polyester polyols with various functional groups and the assessment of the potential for their use. However, there are no review articles on this topic in recent years. In this regard, it is relevant to generalize the latest achievements in the field of synthesis, properties and application of hyperbranched polyester polyols with terminal oxygen, nitrogen, silicon, sulfur and organophosphorus fragments. The advantage of hyperbranched polyester polyols of the Boltorn H series is their industrial availability, biodegradability, nanoscale, non-toxicity and high solubility in various polar solvents due to short monomer units, as well as the presence of reactive terminal hydroxyl groups. Functionalization of hyperbranched polyester polyols at hydroxyl groups is mainly carried out by addition of acid anhydrides, iso(thio)cyanates, alkenes, lactides, lactones, lactams, epoxy compounds or reactions with halogenated compounds(alkyl halides, acid chlorides). In some cases, for the functionalization of polyester polyols special linkers are used, such as acid chlorides of unsaturated or dicarboxylic acids, diisocyanates, etc., which provide covalent bonding of the hyperbranched polymer with the target functional group. The obtained derivatives of hyperbranched polyesters are widely used in such areas as biomedicine, pharmacy, paints and varnishes, they are also used as catalysts, membranes, multifunctional coatings, plasticizers and polymer stabilizers.展开更多
Renewable 2,5-furandicarboxylic acid-based polyesters are one of the most promising materials for achieving plastic replacement in the age of energy and environmental crisis.However,their properties still cannot compe...Renewable 2,5-furandicarboxylic acid-based polyesters are one of the most promising materials for achieving plastic replacement in the age of energy and environmental crisis.However,their properties still cannot compete with those of petrochemical-based plastics,owing to insufficient molecular and/or microstructure designs.Herein,we utilize the Ti_(3)C_(2)T_(x)-based MXene nanosheets for decorating carbon nanotube(CNT)and obtaining the structurally stable and highly dispersed dendritic heterostructured MXene@CNT,that can act as multi-roles,i.e.,polycondensation catalyst,crystal nucleator,and interface enhancer of polyester.The biobased MXene@CNT/polybutylene furandicarboxylate(PBF)(denoted as MCP)nanocomposites are synthesized by the strategy of“in situ catalytic polymerization and hot-pressing”.Benefiting from the multi-scale interactions(i.e.,covalent bonds,hydrogen bonds,and physical interlocks)in hybrid structure,the MCP presents exceptional mechanical strength(≈101 MPa),stiffness(≈3.1 GPa),toughness(≈130 MJ m^(-3)),and barrier properties(e.g.,O_(2)0.0187 barrer,CO_(2)0.0264 barrer,and H2O 1.57×10^(-14) g cm cm^(-2) s Pa)that are higher than most reported bio-based materials and engineering plastics.Moreover,it also displays satisfactory multifunctionality with high reprocessability(90%strength retention after 5 recycling),UV resistance(blocking 85%UVA rays),and solvent-resistant properties.As a state-of-art high-performance and multifunctional material,the novel bio-based MCP nanocomposite offers a more sustainable alternative to petrochemical-based plastics in packaging and engineering material fields.More importantly,our catalysis-interfacial strengthening integration strategy opens a door for designing and constructing high-performance bio-based polyester materials in future.展开更多
Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly ...Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes.展开更多
The development of sustainable,eco-friendly polyesters from renewable resources is crucial for reducing dependence on petroleum-based plastics.However,despite advances in microbial pro-duction of bioplastics,significa...The development of sustainable,eco-friendly polyesters from renewable resources is crucial for reducing dependence on petroleum-based plastics.However,despite advances in microbial pro-duction of bioplastics,significant challenges remain in achieving high conversion efficiency and scalability for industrial applications.This study is the first to report the synthesis of a 100%bio-based polyester using both 1,12-dodecanedioic acid(1,12-diacid)and 1,12-dodecanediol(1,12-diol)via a two-step microbial bioconversion from a single plant oil-derived alkane.An engineered Candida tropicalis strain produced 150 g/L of 1,12-diacid with a productivity of 1.53 g/(L·h)in a 5 L fed-batch system using a two-phase biotransformation strategy.Escherichia coli engineered to express carboxylic acid reductase,which reduces carboxylic acids to aldehydes,and its ac-tivation enzyme phosphopantetheinyl transferase,converted 1,12-diacid into 68 g/L 1,12-diol with a productivity of 1.42 g/(L·h)in a 5 L fed-batch system,representing high titer and pro-ductivity for microbial production of long-chainα,ω-diols.Both monomer production processes were successfully scaled up to a 50 L pilot fermenter,validating their potential for industrial implementation.A highly efficient downstream purification process was developed,achieving>98%purity and recovery rates for both monomers.The bio-derived monomers enabled the syn-thesis of polyesters with molecular weight and thermal characteristics similar to petroleum-based monomers of the same chemical structure.This integrated approach establishes a robust and scal-able microbial platform that converts renewable lipid feedstocks into fully bio-based polyesters,thereby demonstrating an environmentally sustainable and industrially viable route to circular bioeconomy-based polyester production.展开更多
PU,or polyurethane,features a repeating urethane group(-NH-COO-)in its molecular structure.Traditionally,PUs are synthesized from isocyanate and polyol compounds derived from fossil resources through polymerization re...PU,or polyurethane,features a repeating urethane group(-NH-COO-)in its molecular structure.Traditionally,PUs are synthesized from isocyanate and polyol compounds derived from fossil resources through polymerization reactions.The depletion of fossil fuels and the increasing climate problems call for the expansion of more renewable sources of chemicals,such as modern biomass.However,the conversion of biomass into chemicals is challenging due to the inherent molecular complexity of its composition.In recent years,advances in green chemistry have led researchers to focus on developing bio-based polyurethanes by sourcing polyols,isocyanates,and chain extender precursors from biological materials.This paper focuses on the preparation of polyols,non-isocyanates and bio-based chain extenders from bio-based materials such as vegetable oils,lignin,sugars,and rosin.The synthetic routes and properties of several bio-based polyurethane materials are analyzed.Additionally,it discusses the current status,future challenges,and potential applications of bio-based polyurethane materials across various fields.展开更多
The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance a...The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.展开更多
文摘Recently, hyperbranched polymers(HBPs), which differ significantly in structure and properties from linear, cross-linked and branched analogs, have become increasingly important. HBP have a spatial unloaded core and a shell of branched monomer units(dendrons), in which functional groups are predominantly located in the surface layer. The size of macromolecules ranges from 2 nm to 100 nm. Currently, there are a fairly large number of publications in the literature devoted to the modification of hyperbranched polyester polyols with various functional groups and the assessment of the potential for their use. However, there are no review articles on this topic in recent years. In this regard, it is relevant to generalize the latest achievements in the field of synthesis, properties and application of hyperbranched polyester polyols with terminal oxygen, nitrogen, silicon, sulfur and organophosphorus fragments. The advantage of hyperbranched polyester polyols of the Boltorn H series is their industrial availability, biodegradability, nanoscale, non-toxicity and high solubility in various polar solvents due to short monomer units, as well as the presence of reactive terminal hydroxyl groups. Functionalization of hyperbranched polyester polyols at hydroxyl groups is mainly carried out by addition of acid anhydrides, iso(thio)cyanates, alkenes, lactides, lactones, lactams, epoxy compounds or reactions with halogenated compounds(alkyl halides, acid chlorides). In some cases, for the functionalization of polyester polyols special linkers are used, such as acid chlorides of unsaturated or dicarboxylic acids, diisocyanates, etc., which provide covalent bonding of the hyperbranched polymer with the target functional group. The obtained derivatives of hyperbranched polyesters are widely used in such areas as biomedicine, pharmacy, paints and varnishes, they are also used as catalysts, membranes, multifunctional coatings, plasticizers and polymer stabilizers.
基金financial supports from the National Natural Science Foundation of China(Grant No.NSFC52473104)National Key R&D Program of China(Grant No.2022YFC2104500)+3 种基金Zhejiang Provincial Natural Science Foundation of China(Grant No.Y24B040002)Ningbo 2025 Key Scientific Research Programs(Grant No.2022Z160)the China Postdoctoral Science Foundation(Grant No.2023M733601)the Ningbo Natural Science Foundation(Grant No.2023I333&2023J409).
文摘Renewable 2,5-furandicarboxylic acid-based polyesters are one of the most promising materials for achieving plastic replacement in the age of energy and environmental crisis.However,their properties still cannot compete with those of petrochemical-based plastics,owing to insufficient molecular and/or microstructure designs.Herein,we utilize the Ti_(3)C_(2)T_(x)-based MXene nanosheets for decorating carbon nanotube(CNT)and obtaining the structurally stable and highly dispersed dendritic heterostructured MXene@CNT,that can act as multi-roles,i.e.,polycondensation catalyst,crystal nucleator,and interface enhancer of polyester.The biobased MXene@CNT/polybutylene furandicarboxylate(PBF)(denoted as MCP)nanocomposites are synthesized by the strategy of“in situ catalytic polymerization and hot-pressing”.Benefiting from the multi-scale interactions(i.e.,covalent bonds,hydrogen bonds,and physical interlocks)in hybrid structure,the MCP presents exceptional mechanical strength(≈101 MPa),stiffness(≈3.1 GPa),toughness(≈130 MJ m^(-3)),and barrier properties(e.g.,O_(2)0.0187 barrer,CO_(2)0.0264 barrer,and H2O 1.57×10^(-14) g cm cm^(-2) s Pa)that are higher than most reported bio-based materials and engineering plastics.Moreover,it also displays satisfactory multifunctionality with high reprocessability(90%strength retention after 5 recycling),UV resistance(blocking 85%UVA rays),and solvent-resistant properties.As a state-of-art high-performance and multifunctional material,the novel bio-based MCP nanocomposite offers a more sustainable alternative to petrochemical-based plastics in packaging and engineering material fields.More importantly,our catalysis-interfacial strengthening integration strategy opens a door for designing and constructing high-performance bio-based polyester materials in future.
文摘Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes.
基金supported by the KEIT R&D Program(No.20025698&00432188)funded by the Ministry of Trade,Industry&Energy(Republic of Korea).
文摘The development of sustainable,eco-friendly polyesters from renewable resources is crucial for reducing dependence on petroleum-based plastics.However,despite advances in microbial pro-duction of bioplastics,significant challenges remain in achieving high conversion efficiency and scalability for industrial applications.This study is the first to report the synthesis of a 100%bio-based polyester using both 1,12-dodecanedioic acid(1,12-diacid)and 1,12-dodecanediol(1,12-diol)via a two-step microbial bioconversion from a single plant oil-derived alkane.An engineered Candida tropicalis strain produced 150 g/L of 1,12-diacid with a productivity of 1.53 g/(L·h)in a 5 L fed-batch system using a two-phase biotransformation strategy.Escherichia coli engineered to express carboxylic acid reductase,which reduces carboxylic acids to aldehydes,and its ac-tivation enzyme phosphopantetheinyl transferase,converted 1,12-diacid into 68 g/L 1,12-diol with a productivity of 1.42 g/(L·h)in a 5 L fed-batch system,representing high titer and pro-ductivity for microbial production of long-chainα,ω-diols.Both monomer production processes were successfully scaled up to a 50 L pilot fermenter,validating their potential for industrial implementation.A highly efficient downstream purification process was developed,achieving>98%purity and recovery rates for both monomers.The bio-derived monomers enabled the syn-thesis of polyesters with molecular weight and thermal characteristics similar to petroleum-based monomers of the same chemical structure.This integrated approach establishes a robust and scal-able microbial platform that converts renewable lipid feedstocks into fully bio-based polyesters,thereby demonstrating an environmentally sustainable and industrially viable route to circular bioeconomy-based polyester production.
基金supported by the China Postdoctoral Science Foundation(No.200902090)Tianjin Enterprise Science and Technology Commissioner Project(No.21YDTPJC00570).
文摘PU,or polyurethane,features a repeating urethane group(-NH-COO-)in its molecular structure.Traditionally,PUs are synthesized from isocyanate and polyol compounds derived from fossil resources through polymerization reactions.The depletion of fossil fuels and the increasing climate problems call for the expansion of more renewable sources of chemicals,such as modern biomass.However,the conversion of biomass into chemicals is challenging due to the inherent molecular complexity of its composition.In recent years,advances in green chemistry have led researchers to focus on developing bio-based polyurethanes by sourcing polyols,isocyanates,and chain extender precursors from biological materials.This paper focuses on the preparation of polyols,non-isocyanates and bio-based chain extenders from bio-based materials such as vegetable oils,lignin,sugars,and rosin.The synthetic routes and properties of several bio-based polyurethane materials are analyzed.Additionally,it discusses the current status,future challenges,and potential applications of bio-based polyurethane materials across various fields.
基金financially supported by the Provincial Project of Science and Technology(No.2023112258)Tianshan Talent Training Program(No.2024TSYCCX0112)+1 种基金Talent Introduction and Start Foundation for Young Scientists of Shihezi University(No.2022ZK004)Program for Young Innovative Talents of Shihezi University(No.CXFZ202302)。
文摘The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.
