CAJ | 학술논문

通过熔融共混法制备了聚乳酸（PLA）/乙烯-乙酸乙烯酯共聚物（EVA）共混物，采用SEM、DSC、旋转流变仪等研究了VA质量分数为28%，熔体流动速率（MFR）不同的EVA对PLA/EVA共混物性能的影响。结果表明，EVA熔体流动速率越小，其在PLA基体中分散越均匀，EVA颗粒粒径也越小。共混物的结晶度随EVA熔体流动速率的增大而增大，但 PLA的玻璃化转变温度（Tg）基本不受 EVA的影响。PLA/EVA共混物的复数黏度和储能模量均随 EVA 的熔体流动速率的增高而减小。力学性能测试结果表明，当 EVA 的质量分数为15%时，PLA的断裂伸长率明显升高，冲击强度约是纯PLA的2倍。
통과용융공혼법제비료취유산（PLA）/을희-을산을희지공취물（EVA）공혼물，채용SEM、DSC、선전류변의등연구료VA질량분수위28%，용체류동속솔（MFR）불동적EVA대PLA/EVA공혼물성능적영향。결과표명，EVA용체류동속솔월소，기재PLA기체중분산월균균，EVA과립립경야월소。공혼물적결정도수EVA용체류동속솔적증대이증대，단 PLA적파리화전변온도（Tg）기본불수 EVA적영향。PLA/EVA공혼물적복수점도화저능모량균수 EVA 적용체류동속솔적증고이감소。역학성능측시결과표명，당 EVA 적질량분수위15%시，PLA적단렬신장솔명현승고，충격강도약시순PLA적2배。
Poly(lactic acid)(PLA)/poly(ethylene-co-vinyl acetate)(EVA) blends were prepared by melt blending. The effects of melt flow rate of EVA (28%VA content) on the morphology,thermal properties and rheological behaviors of PLA/EVA blends were investigated. The results indicated that the EVA phase with smaller particles and better dispersion in the PLA matrix was observed when the EVA with lower melt flow rate was used. With the increase of melt flow rate of EVA,the crystallinity of blends was increased,though the Tg of PLA was hardly affected by the addition of EVA. And the complex viscosity and storage modulus of the blends were decreased. It was demonstrated by mechanical tests that with the addition of 15% EVA into PLA,an obvious increase in elongation at break was observed,and the izod notched impact strength was about two times higher than the pure PLA.