单体和低聚物的含量对聚酰胺6切片性能的影响  

Effects of monomer and oligomer content in polyamide 6 pellets on their properties

作　　者：郭银涛 王勇军 吕汪洋[1] GUO Yintao;WANG Yongjun;LÜWangyang(National Engineering Laboratory for Textile Fiber Materials and Processing Technology,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学纺织纤维材料与加工技术国家工程实验室,杭州310018

出　　处：《浙江理工大学学报（自然科学版）》2024年第2期174-179,共6页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：浙江省自然科学基金项目(LDQ23E030001)。

摘　　要：采用溶解/沉淀法对聚酰胺6(PA6)中的单体及低聚物进行提取,利用液相色谱/飞行时间质谱/二极管阵列检测器(LC-TOF-MS-PDA)和聚合物色谱/多角度激光散射/示差折光检测器(APC-MALLS-RID)联用方法测定PA6中单体和低聚物含量、低聚物组成及PA6的分子量和分布;通过热重分析仪、差示扫描量热仪和二维广角X射线衍射仪分析PA6切片中单体低聚物含量对切片热性能和结晶性能的影响。结果表明:物理再生PA6(pr-PA6)和化学再生PA6(cr-PA6)中单体及环状低聚物含量分别为2.079%和1.578%,比原生PA6(PA6)分别高0.683%和0.182%,其中再生PA6切片中单体、环状二聚体和环状三聚体含量高于原生PA6切片。PA6、pr-PA6和cr-PA6的分子量分别为19620、20840 g/mol和22210 g/mol,分子量分布系数分别为1.47、1.56和1.49;三种PA6切片的最大分解温度无明显变化。与原生PA6切片相比,再生PA6切片的结晶峰温度向高温区偏移,结晶温度从PA6的176℃增加至pr-PA6的185℃,且pr-PA6和cr-PA6切片中α晶型的相对含量增加。该研究可为提高PA6材料的热性能及结晶性能提供理论基础。Monomers and oligomers from polyamide 6(PA6)were extracted by dissolution/precipitation method,a combination of liquid chromatography/time flight mass spectrometry/photodiode array detector(LC-TOF-MS-PDA)and a polymer chromatography/multi-angle laser-light-scattering/refractive index detector(APC-MALLS-RID)was used to measure the monomer and oligomer content and oligomer composition of PA6,PA6 molecular weight and its distribution in PA6.The effects of the monomer and oligomer content on the thermal and crystallization properties of PA6 pellets were analyzed by thermogravimetric analyzer,differential scanning calorimeter and two-dimensional wide-angle X-ray diffractometer.The results indicate that the monomer and cyclic oligomer contents in physically recycled PA6(pr-PA6)and chemically recycled PA6(cr-PA6)pellets were 2.079%and 1.578%,respectively,0.683%and 0.182%higher than those in the original PA6(PA6)pellets,while the monomer,cyclic dimer and cyclic trimer contents in the recycled PA6 pellets were higher than those of the original PA6 pellets.The molecular weights of PA6,pr-PA6 and cr-PA6 were 19620 g/mol,20840 g/mol and 22210 g/mol,respectively,with the molecular weight distribution coefficients of PA6,pr-PA6 and cr-PA6 being 1.47,1.56 and 1.49,respectively.The maximum decomposition temperatures of the three PA6 pellets did not change significantly.Compared with the original PA6 pellets,the crystallization peak temperature of regenerated PA6 pellets shifted to the high temperature region,and the crystallization temperature increased from 176℃for PA6 to 185℃for pr-PA6,and the relative content ofαcrystalline forms in pr-PA6 and cr-PA6 pellets increased.This study can provide a theoretical basis for improving the thermal and crystallization properties of PA6 materials.

关 键 词：PA6切片 单体 低聚物 液相色谱/飞行时间质谱/二极管阵列检测器 结晶 

分 类 号：TQ317.2[化学工程—高聚物工业]