Study On The Preparation And Properties Of IPDI Waterborne Polyurethane

Waterborne polyurethane is dispersible in water medium, which has not only the excellent properties of solvent-borne polyurethane with good resistance, great adhesion, as well as outstanding toughness combined with good flexibility, but also advantages of incombustibility, low- odor and environmental friendliness. The environmental regulation and the increasing concern of people' s environmental protection are leading to the replacement of solvent-borne polyurethane, and nowdays it is widely used in industries such as coatings or adhesives . But domestic research on it was limited by sorts of conditions, which is basically in primitive stage.Now, many concentrationses of raw materials that uses of research of local waterbrone polyurethane are in the type of toluene diisocyanate;To the waterbrone polyurethane of the type aliphaic cliisocyanate research less. Along with the living level of people of continuously increase, demand environmental protection, healthand high performance product increasingly and urgently, the green chemicals gradually become the future development's main.current. A series of aliphatic waterborne polyurethanes were prepared from isophorone diisocyanate (IPDI), polyether and dimethylolpropanic acid (DMPA). The COOH groups were neutralized by triethylamine (TEA). The effects of soft-segment structure and molecular weight, DMPA amount, neutralizer on mechanical properties of the emulsion cast films were investigated. The experimental data showed that the mechanical properties of waterborne PU films depend heavily on the structure and molecular weight of soft segments. As the molecular weight of soft segments Increases, emulsion stable of waterborne PU films decrease, while elongation and tensile strength increase. DMPA amount also influences the mechanical properties of waterborne PU films. As DMPA amount increases, emulsion stable and tensile strength of waterborne PU films increase, while elongation and solvent-resistance decrease; therefore on condition that PU emulsion is stable, the content of DMPA should is possibly lower . As TEA amount increases also leads higher elongation. To compare TDI PU emulsion cast film, IPDI PU emulsion cast film is superior onlight-resistance.