摘要
为防止等规聚丙烯(PP)在过氧化二异丙苯(DCP)作用下降解,同时促进其交联,采用硫磺为交联助剂,二硫化四甲基秋兰姆(TMTD)为促进剂对PP进行改性。通过对改性PP的熔融指数(MFR)及力学性能的测定表明,加入硫磺后相比纯PP其MFR值降低为原来的1/3,而冲击强度提高了近240%,断裂伸长率提高了70%。通过差示扫描量热(DSC)和动态热力学分析(DMA)研究表明,在硫磺的作用下,大分子自由基稳定性提高,PP降解受到抑制,链段间产生了交联或接枝结构。
To prevent the degradation of isotactic polypropylene at the presence of dicumyl peroxide （DCP） and initiate the crosslinking of polypropylene（PP） at the same time, sulfur was selected as the crosslinking agent and tetramethyl thiuram disulfide （TMTD） as the accelerator to modify PP. Through the measurements of mechanical property and melt flow index（MFR）, it is found that MFR of the modified PP reduces to 1/3 that of the neat PP, while the impact strength is improved by 240% and the elongation at break by 70 %, compared with those of the unmodified coordinate. The modified PP was characterized by dynamic mechanical thermal analysis （DMA） and differential scanning calorimetry （DSC）. The results reveal that the stability of the macroradicals is improved, the degradation of PP is inhibited and the crosslinked or branched structure is formation between the macromolecule chains.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2013年第7期56-59,共4页
Polymer Materials Science & Engineering
关键词
等规聚丙烯
过氧化二异丙苯
硫磺
交联
isotactie polypropylene
dicumyl peroxide
sulfur
crosslinking
