麦秸秆外表面膜及异氰酸酯对麦秸与LDPE界面结合的影响

Effects of Outer Surface Membrane of Wheat Stalk and Isocyanate on Interfacial Bond between Wheat Stalk and LDPE

采用物理及力学性能以及界面结合形态分析相结合的方法,研究了麦秸秆外表面膜及异氰酸酯(PAPI)对麦秸与低密度聚乙烯(LDPE)两相界面结合的影响。研究结果表明:1.3% PAPI可显著提高麦秸/回收LDPE复合材料干态及2 h沸水后内结合强度、静曲强度及弹性模量,对24 h吸水厚度膨胀率的降低改善不大;麦秸秆外表面膜具有改善麦秸与LDPE两相界面结合作用;PAPI可将麦秸与回收LDPE、麦秸秆外表面与新LDPE两相界面由相分离转变为相连续。PAPI具有有效改善麦秸与LDPE两相界面结合强度的作用。

The effects of outer surface membrane of wheat stalk and methylene-bridged polyphenylene polyisocyanate （PAPI） on the interfacial bond between wheat stalk and low density polyethylene （LDPE） were investigated by methods of physical determination combinated with interface morphological structure analysis. The results show that with the addition of 1.3 % PAPI, dry internal bonding strength, internal bonding strength of boiling-water treatment for 2 h, modulus of rupture and modulus of elasticity of the composite are increased significantly, while thickness expansion rate of water absorption for 24 h is decreased insignificantly. The outer surface membrane of wheat stalk improves the interface bond between wheat straw and LDPE. PAPI changes the interphase between wheat stalk and recycled LDPE, as well as between outer surface of wheat stalk with fresh LDPE from two-phase structure into continuous structure ,which behaves significant effect of improving interface bonding strength.