原位改性浇铸尼龙6复合材料的合成与表征

Synthesis and characterization of in-situ modified monomer cast nylon 6 composites

为了提高单体浇铸尼龙6(MCPA6)的综合性能,在MCPA6合成体系中添加乙烯-辛烯共聚物(POE)、聚氨酯包覆空心玻璃微珠(TPU@HGM)进行原位改性,制备了MCPA6/POE和MCPA6/POE/TPU@HGM复合材料,研究POE及POE/TPU@HGM对材料结构和性能的影响。傅里叶变换红外光谱表征结果显示合成的聚合物为MCPA6。力学性能测试结果表明,POE加入可提高材料的断裂伸长率和缺口冲击强度,但会降低拉伸强度;MCPA6/POE/TPU@HGM复合材料的拉伸强度、断裂伸长率、缺口冲击强度与纯MCPA6相比分别提高了32.23%,110.07%,114.36%,实现了增强增韧的效果。POE和TPU@HGM的加入提高了复合材料分解温度和残炭率,热稳定性提高。此外,POE和TPU@HGM对复合材料中MCPA6的结晶有阻碍作用,使MCPA6的结晶温度降低、结晶速度减慢、结晶结构不完善、熔点降低。

In order to improve the comprehensive performances of monomer cast nylon 6(MCPA6),ethylene-octene copolymer(POE)and hollow glass microspheres coated by polyurethane(TPU@HGM)were added to the MCPA6 synthesis system for in-situ modification,then MCPA6/POE and MCPA6/POE/TPU@HGM composites were prepared.The effects of POE and POE/TPU@HGM on the structure and properties of composites were studied.The characterization results of Fourier transform infrared spectrum show that the synthesized polymer is MCPA6.The test results of mechanical properties show that the elongation at break and notched impact strength of the material are improved with introduction POE into MCPA6,but the tensile strength of the material is reduced.Compared with neat MCPA6,the tensile strength,elongation at break and notched impact strength of MCPA6/POE/TPU@HGM composite increase by 32.23%,110.07%and 114.36%respectively,which realizes the effect of reinforcing and toughening.With the addition of POE and TPU@HGM,the decomposition temperature and carbon residue rate of the composite is improved,and the thermal stability of the composite is improved.In addition,the crystallization of MCPA6 in the composite is hindered by POE and TPU@HGM,resulting in a decrease in crystallization temperature,slower crystallization rate,incomplete crystal structure,and lower melting point.