Enzymatic hydrolysis of lysine diisocyanate based polyurethanes and segmented polyurethane ureas by various proteases

详细信息    查看全文

• 作者：Noboru Yamamoto ; Atsuyoshi Nakayama ; Maki Oshima ; Norioki Kawasaki ; Sei-ichi Aiba
• 关键词：Polyurethane ; Biodegradation ; Enzymatic hydrolysis ; Protease ; Lysine diisocyanate
• 刊名：Reactive and Functional Polymers
• 出版年：2007
• 出版时间：November 2007
• 年：2007
• 卷：67
• 期：11
• 页码：1338-1345
• 全文大小：165 K

文摘

This work studies the enzymatic degradation of polyurethanes (PUs) and segmented polyurethane ureas (SPUUs) derived from lysine diisocyanate (LDI) by various proteases. Thiol proteases, such as papain, bromelain, and ficin, showed high activity on PUs. Protease K and chymotrypsin also hydrolyzed the PUs. For almost all SPUUs, papain showed high activity. For example, LDI/poly(caprolactone) diol (M_w = 1250)/ethylene diamine (2/1/1) was hydrolyzed to 43 % under the same conditions. The water-soluble degradation products of a polyurethane, LDI/BD (1/1), and two model compounds treated with papain were studied with NMR and GPC analysis. From the results, it was evident that the pendant methyl ester group in LDI was rapidly hydrolyzed, followed by slow hydrolysis of urethane bonds in the backbone chain.