メンシュトキン反応によるポリウレタンイオノマー生成反応
スポンサーリンク
概要
- 論文の詳細を見る
Polyurethane ionomers were prepared by the Menschutkin reaction of diaminourethane prepolymer (DAU) and dihalides. The reaction kinetics were studied in dimethylformamide by following the amino groups. DAU was prepared by the reaction of 2-dimethylaminoethanol and isocyanated-terminated prepolymer obtained from polytetramethylene glycol and 4,4'- diphenylmethane diisocyanate. Dihalides used were p-xylylene dichloride (XDC) and 1,6-dibromohexane (DBH). The reaction proceeded by a nucleophilic bimolecular substitution (S_N, 2) mechanism, thus the rate equation was, v=k [DAU][Dihalide] . In the reaction of DAU and XDC, this equation held good until about 50% of the reaction, but above 50% a deviation was observed and simultaneously the solution became cloudy. This deviation may be caused by the phase-seperation due to the formation of a microionic lattice. On the other hand, the reaction of DAU and DBH proceeded in a homogeneous system and no deviation was observed. The reaction of DAU and XDC was fairly faster than that of DAU and DBH owing to the structual characteristic of XDC to stabilize the transition state with delocalization. The activated energy (E_A) was 10.8 kcal/mol and log of the frequency factor (log A) 6.30 for the DAU/XDC system ; 11.6 kcal/mol and 5.99 for the DAU/DBH system, respectively. The reaction was accelerated in aprotic solvents in the order of dimethylacetamide< dimethylformamide/methanol< dimethylformamid < dimethylsulfoxide. The results obtained from the model reaction of N,N,N',N'-tetramethylhexamethy lenediamine and dihalides were also discussed.
- 近畿大学の論文
- 1977-12-01
著者
関連論文
- 橋かけポリウレタンイオノマーの合成と粘弾性
- セグメンティッドポリウレタンイオノマーの合成と粘弾性
- メンシュトキン反応によるポリウレタンイオノマー生成反応
- ポリウレタンの力学的性質におよぼす架橋法の影響
- イソシアヌレート架橋ポリウレタンの粘弾性II : ポリオキシテトラメチレングリコール基剤ポリウレタン
- イソシアヌレート架橋ポリウレタンの粘弾性
- イソシアヌレート型架橋ポリウレタンの性質