Foaming behavior of poly(lactic acid)/polyolefin elastomer blends
To study the effect of interfacial interaction of poly(lactic acid)(PLA)blends on cell structure,polyolefin elastomer(POE)and POE grafted with maleic anhydride(POE-g-MAH)were chosen to mix with PLA to prepare PLA/POE and PLA/POE-g-MAH blends,and then the blend foams were prepared via batch foaming process.First,the dispersion of POE and POE-g-MAH in PLA were observed using scanning electron microscope(SEM).Then,the rheological behavior of PLA/POE and PLA/POE-g-MAH blends were studied with rheometer.Last,the cell structure of PLA/POE and PLA/POE-g-MAH blend foams were studied with SEM,the expansion ratio of the foams was obtained via measuring the density before and after foaming,and the effect of inter-facial interaction on cell structure was discussed.The results show that with increase in elastomer content,the phase domains of POE and POE-g-MAH both increase,and the latter has smaller phase domains.With increase in POE and POE-g-MAH content,the complex viscosity and storage modulus of both blends increase.POE-g-MAH has stronger interfacial interaction with PLA,and resultantly,the complex viscosity and storage modulus of the blend increase more significantly.With elastomer content of 10% and 20%,the heterogeneous cell nucleation is enhanced for PLA blends with POE,and hence,the cell size is smaller.The cell growth is facilitated for PLA blends with POE-g-MAH,and hence,the cell size is larger.For foams prepared at 90℃,PLA/POE-g-MAH10 and PLA/POE-g-MAH20 have larger expansion ratio than PLA/POE10 and PLA/POE20.
poly(lactic acid)polyolefin elastomerpolyolefin elastomer grafted with maleic anhydrideblendfoaming behavior
NETL
NSTL
万方数据
