合成树脂及塑料
閤成樹脂及塑料
합성수지급소료
CHINA SYNTHETIC RESIN AND PLASTICS
2014年
2期
71-75
,共5页
李艳东%乔辉%丁筠%包宽亮
李豔東%喬輝%丁筠%包寬亮
리염동%교휘%정균%포관량
聚乳酸%聚丙烯%低密度聚乙烯%流变性能
聚乳痠%聚丙烯%低密度聚乙烯%流變性能
취유산%취병희%저밀도취을희%류변성능
poly(lactic acid)%polypropylene%low density polyethylene%rheological behavior
采用毛细管流变仪考察了温度、剪切速率、预热时间对聚乳酸(PLA)、聚丙烯(PP)、低密度聚乙烯(LDPE)流变性能的影响。结果表明:PLA属切力变稀流体,在210℃时的非牛顿指数为0.68,而该温度下PP的非牛顿指数为0.56,LDPE为0.49;在剪切速率为100~2000s-1时,PLA的黏流活化能为61.51~141.52kJ/mol,PP为14.6~31.92kJ/mol,LDPE为13.89~36.47kJ/mol;在低剪切速率时,增加预热时间不仅使PLA的黏度明显下降,而且使其非牛顿指数和黏流活化能增加,当预热时间从150s增加到300s时,PLA在210℃的非牛顿指数从0.44增加到0.68,剪切速率为100~5000s-1的黏流活化能从32.99~91.67kJ/mol增加到50.40~141.52kJ/mol。
採用毛細管流變儀攷察瞭溫度、剪切速率、預熱時間對聚乳痠(PLA)、聚丙烯(PP)、低密度聚乙烯(LDPE)流變性能的影響。結果錶明:PLA屬切力變稀流體,在210℃時的非牛頓指數為0.68,而該溫度下PP的非牛頓指數為0.56,LDPE為0.49;在剪切速率為100~2000s-1時,PLA的黏流活化能為61.51~141.52kJ/mol,PP為14.6~31.92kJ/mol,LDPE為13.89~36.47kJ/mol;在低剪切速率時,增加預熱時間不僅使PLA的黏度明顯下降,而且使其非牛頓指數和黏流活化能增加,噹預熱時間從150s增加到300s時,PLA在210℃的非牛頓指數從0.44增加到0.68,剪切速率為100~5000s-1的黏流活化能從32.99~91.67kJ/mol增加到50.40~141.52kJ/mol。
채용모세관류변의고찰료온도、전절속솔、예열시간대취유산(PLA)、취병희(PP)、저밀도취을희(LDPE)류변성능적영향。결과표명:PLA속절력변희류체,재210℃시적비우돈지수위0.68,이해온도하PP적비우돈지수위0.56,LDPE위0.49;재전절속솔위100~2000s-1시,PLA적점류활화능위61.51~141.52kJ/mol,PP위14.6~31.92kJ/mol,LDPE위13.89~36.47kJ/mol;재저전절속솔시,증가예열시간불부사PLA적점도명현하강,이차사기비우돈지수화점류활화능증가,당예열시간종150s증가도300s시,PLA재210℃적비우돈지수종0.44증가도0.68,전절속솔위100~5000s-1적점류활화능종32.99~91.67kJ/mol증가도50.40~141.52kJ/mol。
The rheological properties of poly(lactic acid) (PLA), polypropylene (PP) and low density polyethylene (LDPE) were studied as a function of temperature, shear rate and warm-up time. The results indi-cate that PLA is a shear thinning material, whose non-Newtonian index is 0.68 at 210 ℃, while those of PP and LDPE are 0.56 and 0.49, respectively; meanwhile the viscous flow activation energy of PLA is 61.51-141.52 kJ/mol when the shear rate is 100-2 000 s-1. and for PP and LDPE, they are 14.60-31.92 kJ/mol and 13.89-36.47 kJ/mol, respectively. The viscosity of PLA decreases remarkably while the non-Newtonian index and viscous flow activation energy of PLA rises as the warm-up time increases at low shear rates. The non-Newtonian index of PLA increases from 0.44 to 0.68 when the warm-up time is extended from 150 seconds to 300 seconds at 210 ℃. And the viscous flow activation energy of PLA rises significantly from 32.99-91.67 kJ/mol to 50.40-141.52 kJ/mol with the shear rate in the range of 100-5 000 s-1.