车身反光贴用聚氨酯胶粘剂的研制

以结晶性聚酯多元醇、直链二醇扩链剂、异氰酸酯和纳米助剂等为主要原料,制备出一种高粘接强度、耐老化性能优良的车身反光贴用PU(聚氨酯)胶粘剂。分析了聚酯多元醇的种类及其Mr(相对分子质量)、扩链剂、异氰酸酯、纳米助剂和催化剂等对PU胶粘剂性能的影响。结果表明:当结晶性聚酯多元醇为Mr=3 000的聚己二酸-1,4-丁二醇酯、扩链剂为1,6-己二醇(HDO)、异氰酸酯为1,6-己二异氰酸酯(HDI)、催化剂为有机铋类(BiCAT 8108)且w(催化剂)=0.03%(相对于反应物总质量而言)、n(聚酯多元醇)∶n(扩链剂)=1∶0.3和w(气相白炭黑)=0.2%～0.3%(相对于反应物总质量而言)时,PU胶粘剂的综合性能相对最好。

Study on preparing polyurethane adhesive for auto-reflective stickers

With crystal polyester polyols,chain extender with linear-chain diol,isocyanate and nano-additives as main raw materials,a polyurethane(PU) adhesive with high bonding strength and good aging-resistance was prepared for auto-reflective stickers.The influences of types and Mr(molecular weight) of polyester polyols,chain extenders,isocyanates,nano-additives and catalysts were analysed on the properties of PU adhesive.The results showed that the PU adhesive had the reversely best combination property when polybutylene adipate with Mr=3 000 was used as a crystal polyester polyols,hexamethylene diisocyanate(HDI) was used as an isocyanate,mass fraction of organic bismuth(BiCAT 8108) as catalyst was 0.03% in total reactants,molar ratio of n(polyester polyol)∶n(1,6-hexanediol as chain extender) was 1∶0.3 and mass fraction of fumed silica was 0.2%-0.3% in total reactants.