由含二酸及二異氰酸酯(-NCO)官能基與次乙亞胺(Aziridine)來合成兩系列含甲醯次乙亞胺官能基的架橋劑,其結構鑑定可由/sup 1/H-NMR、/sup 13/C-NMR及IR光譜確定。 以不同比例之架橋劑加入水性聚胺基甲酸乙酯(PU)中,架橋劑可以穩定的存在鹼性條件下,但在乾燥過程中pH值降低,將會與水性PU分子側鏈上羧酸基在常溫下形成開環架橋反應。測量乾膜的膠含量、接觸角、吸水性、吸乙醇性以及抗張強度、動態機械熱分析(DMTA)等機械性質,證明交聯密度的增加對機械性質的改善。並且以環氧樹脂配合其中一種架橋劑,先後加入水性PU中,以期分別與水性PU的胺基及羧酸基反應。以達到雙重架橋的效果。 Two series of acylaziridinyl compounds were synthesized from the reactions of aziridine with adipic acid and polyisocyanates, respectively. These prepared di- function aziridinyl compounds were identified by nmr and ir spectroscopies. A ring opening reaction between an aziridinyl compound with acetic acid were demonstrated. These di-aziridinyl compounds would react with carboxylic groups of aqueous-based PU and function as a PU cross-linker. The curing reaction of these curing agents took place at ambient temperature under an acidic environment, however, they were stable at an alkaline conditions. The curing behaviors of these curing agents toward aqueous-based PU were evaluated by the measurements of gel content, contact angle, water- or alcohol-uptake, tensile strength and elongation of PU films. Furthermore, epoxy resins were applied as a second curing agent for aqueous-based PU dispersions. The thermal properties of these dual-curing PU system were also monitored by thermo- grimetric and dynamic mechanical analyses.
Relation:
第十九屆高分子研討會論文專輯第十二卷第二冊=Proceedings of the 19th ROC Polymer Symposium 1996，頁 45-48
