苏芸金杆菌/淀粉/聚乙烯共混地膜

以玉米淀粉、线型低密度聚乙烯及能在膜上生长的苏芸金杆菌菌粉共混制得淀粉塑料.通过地埋降解试验研究了淀粉塑料中淀粉的降解率,并测定了其物理性能.结果发现地埋降解120天后5%菌粉和50%淀粉的薄膜淀粉降解率达到89.52%,扫描电镜观察大部分淀粉颗粒破碎,出现许多小孔;不加菌粉的淀粉降解率只有35.48%,表明添加的菌粉对淀粉降解有明显的促进作用.物理性能测试结果表明含淀粉40%～50%的共混薄膜有一定的拉伸强度和透光率,可以用作地膜.

STUDIES ON BACILLUS THURINGIENSIS- STARCH- POLYETHYLENE AGRICULTURAL FILMS

Bacillus Thuringiensis(Bt) ,corn starch and LLDPE were blended to produce different degradable films. After they have been buried in soils for 120 days, the degradation rate of starch in the films which contained Bt 0.5% and starch 50 % was 89. 52 % .It was found that most starch granules have been broken by SEM and the surface of starch have a great amount of tiny cells. The degradation rate not adding Bt is only 35.48% . The result indicated that Bt had greatly promoted the degradation of starch in the films. The blending film containing 40%-50% starch has enough tensile strength, transparency, and this filn can be ued for agriculture.