不同结构的成核剂对聚乳酸结晶行为的影响  

Effects of Nucleating Agents with Different Structures on the CrystallizationBehaviors of Polylactic Acid

作　　者：王冉 WANG Ran(Shanxi Provincial Institute of Chemical Industry(Co.,Ltd.),Taiyuan 030000,China)

机构地区：[1]山西省化工研究所(有限公司),山西太原030000

出　　处：《塑料工业》2024年第6期151-158,共8页China Plastics Industry

基　　金：山西省技术创新中心项目(202104010911021)。

摘　　要：为研究不同结构成核剂对聚乳酸(PLA)结晶行为的影响,选用了不同分子结构的市售成核剂(磷酸盐成核剂、酰肼类成核剂和多酰胺类成核剂)。通过红外(FTIR)、差示扫描量热仪(DSC)和偏光显微镜(POM)等仪器研究了成核剂的引入对PLA结构和结晶行为的影响。结果表明,不同结构成核剂在熔融共混的过程不会改变PLA的分子结构,但均能不同程度地消除或降低PLA冷结晶诱导期,细化PLA的球晶和提高PLA的结晶温度。其中,苯基磷酸锌成核剂(TMC-200)细化PLA球晶的能力最强;在不同升温速率下,含TMC-200成核剂的PLA复合材料(PLA-200)的二次升温DSC曲线上未见明显冷结晶峰;同时TMC-200成核剂可将纯PLA低于3%的结晶度提高至30%以上,PLA-200复合材料的结晶峰温度保持在100℃以上,PLA-200复合材料的结晶活化能下降至119.2 kJ/mol。To investigate the effects of different nucleating agents on the crystallization behaviors of polylactic acid(PLA),commercially available nucleating agents with different molecular structures(phosphate nucleating agent,hydrazide nucleating agent and multiamide nucleating agent)were selected.The effects of nucleating agents on the structures and crystallization behaviors of PLA were studied by using instruments such as Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),and polarizing microscopy(POM).The results show that different nucleating agents do not change the molecular structures of PLA during the melt blending process.However,different nucleating agents could eliminate or reduce the cold crystallization induction periods of PLA to varying degrees,refine the spherical crystals of PLA,and increase the crystallization temperatures of PLA.Among them,the zinc phenylphosphate nucleating agent(TMC-200)has the strongest ability to refine PLA spherulites,and no obvious cold crystallization peak is observed on the secondary heating DSC curves of PLA-200 composite at different heating rates.At the same time,TMC-200 nucleating agent could increase the crystallinity of pure PLA from below 3%to above 30%.In addition,the crystallization peak temperatures of PLA-200 composite maintain above 100℃,and the crystallization activation energy of PLA-200 composite is decreased to 119.2 kJ/mol.

关 键 词：聚乳酸 成核剂 结晶度 结晶活化能 细化晶粒 

分 类 号：TQ321.2[化学工程—合成树脂塑料工业]