聚异氰酸酯与淀粉基试样反应产物的光电子能谱分析  

ESCA Analysis on Reaction Product of PMDI to Starch-Based Sample

作　　者：时君友[1,2,3] 王垚[1] 顾继友[3] 

机构地区：[1]清华大学化学工程系,北京100084 [2]北华大学木材科学与工程系,吉林吉林132013 [3]东北林业大学材料科学与工程学院,黑龙江哈尔滨150040

出　　处：《高分子材料科学与工程》2008年第11期74-78,共5页Polymer Materials Science & Engineering

基　　金：科技部农业转化资金项目(03EFN212200069);吉林省科技发展计划重点项目(2040204-2-1);国家重点基础研究项目(973计划2004CB719706)

摘　　要：为揭示淀粉复合变性前后羟基与水分子对异氰酸酯基反应几率的变化、淀粉基API木材胶粘剂贮存稳定性改善的本质及聚异氰酸酯对淀粉复合变性前后交联固化程度的影响,文中采用化学分析光电子能谱(ESCA)分析聚异氰酸酯(PMDI)与淀粉基试样反应产物的结构,考察淀粉含水率变化对产物结构的影响。结果表明,PMDI与淀粉基试样在130℃等温条件下反应30 min,随原料淀粉基试样含水率的提高,产物中的羰基含量降低,氨基甲酸酯与取代脲之比增高。经分析产物表面及内部羰基含量的差异,证明PMDI更易与复合变性淀粉反应,生成极性更强的氨基甲酸酯,利于木材的胶接。The storage stability and crosslink curing degree of modified starch based-API wood adhesive have been improved compared with conventional starch-based adhesive. To reveal its essence, ESCA was adopted to characterize structural properties of the products of PMDI reacted with starch-based samples for 30 min at constant temperature of 130℃. The effect of water content of the starch reactants on product structures was investigated. The results show that the content of earbonyl decreases and the ratio of carbamic ester to substantial-urea increases when there is an increase in water content of the starch reactants. By analyzing the difference of earbonyl contents between the surface and the interior of the product samples, it can be concluded that PMDI is easier to react with the modified starch into the interior and to form carbarnic ester, which is convenient to bond wood material.

关 键 词：聚异氰酸酯 淀粉 复合变性淀粉 含水率 化学分析光电子能谱 

分 类 号：TQ323.8[化学工程—合成树脂塑料工业]