A novel synthesis of reactive nano-clay polyurethane and its physical and dyeing properties

This study is about polyurea prepolymer, which was synthesized from the extender (N-(2-hydroxyethyl) ethylene diamine, HEDA or ethylene diamine, EDA) with 4,4'-diphenylmethane diisocyanate (MDI), as an intercalative agent to intercalate the organic modified montmorillonite clay. Then, it is further reacted with the polyurethane prepolymer, which is polymerized from the polytetramethylene glycol (PTMG) and MDI, to proceed the intercalative polymerization to form a polyurethane/ clay nanocomposite polymer. The experimental parameters contain the use of polyurea intercalative prepolymer extender and also the contents of organo-clay in the prepolymer etc. We expect to get better mechanical property and also to improve the dyeing properties of nano-clay polyurethane. The polyurethane /clay polymer is synthesized using two-step method: synthesizing the polyurethane pre- polymer from PTMG and MDI and then extended with the polyurea prepolymer modified with the organo-clay. Because the extender HEDA contains side chain of hydroxyl groups, the modified PU can further react with the reactive dye. From the experimental results of the fine structure (X-ray and FT-IR) and mechanical analysis, it is found that the intercalation is successfully achieved. The distance of interlayer spacing is manifestly enlarged. The mechanical properties are significantly improved as the content of organo-clay is increased. Besides, although the dye up-take is decreased with the increasing content of organo-clay, but the water-resistant fastness is improved. (c) 2007 Wiley Periodicals, Inc.