|
The waterborne polyurethane (WPU), based on water as a dispersion medium, polyurethane (PU) particle dispersion which is formed of a transparent or opaque liquid. It not only retains the excellent performance of solvent-based polyurethane abrasion resistance, flexibility, low temperature resistance, fatigue resistance, and has a non-toxic, non-flammable, and does not pollute the environment, the advantages of easy modification, much of the domestic and foreign researchers importance in fabric, leather finishing, adhesives, and fiber reinforced composite materials have a wide range of applications; especially as a thermoplastic resin matrix and ultra-high molecular weight polyethylene (UHMWPE) fiber composites prepared PU-UHMWPE fiber composites can be used in bulletproof materials, cut-resistant gloves, high-strength rope and other fields. This paper work and research achievements mainly divided into the following three aspects: (1) as the main raw material of toluene diisocyanate and polypropylene glycol, 1,4 - butylene glycol, dimethylol propionic acid (DMPA) as a chain extender , triethylamine, as a neutralizer with acetone prepared solid content of 30% of the polyether type in WPU. The DMPA dosage and the NCO / OH molar ratio of (R value) WPU the emulsion appearance, stability, particle size, viscosity, film water absorption and dispersibility of the prepolymer WPU Stability. The results show that with the increase of the amount of DMPA in WPU emulsion of appearance and stability is improved, the particle diameter becomes smaller, the increase in viscosity and film water absorption, the best the DMPA added in an amount of 5 to 6%; With the increase of the R-value in WPU emulsion of the appearance and stability of the reduced viscosity becomes smaller, the particle size and film water absorption was decreased first increase trend, the preferred R value should be controlled at 1.1 to 1.2; used prepolymer was added to go emulsification DI water emulsion can be effective in preventing the generation of gel, prepared WPU emulsion Appearance preferably, a longer storage stability. (2) the use of toluene diisocyanate and poly adipic acid diethylene glycol ester as a main raw material, and a silane coupling agent KH550 modifier, preparation of the silane-modified polyester in WPU. Silane WPU macromolecular chains is introduced into, and dispersed into the water, the silane hydrolysis and condensation occurs and part of the reticulate structure is formed in the polyurethane macromolecular chain ends. The the silane amount of WPU performance. The results showed that in WPU emulsion stability and changes in appearance as KH550 increase in the amount is small, but when the the KH550 amount exceeds 5%, the emulsion stability and appearance deteriorate; increase of KH550 dosage, WPU emulsion particle size, viscosity and WPU film water absorption and showed a tendency to increase in the first decreases after the soft segment glass transition temperature and the film is initially elevated decomposition temperature, the film tensile strength increases, the elongation at break decreases; film with water contact angle, surface tension decreased with the UHMWPE fiber invasive enhanced, the improvement of interfacial adhesion properties. Considering the the KH550 amount of control the best in the 2 to 4% is more appropriate. Adoption the WPU prepolymer stage to join the process of adding a silane coupling agent silane coupling agent is more dispersed, prepared the appearance and stability is good. (3) the use of toluene diisocyanate and polypropylene glycol as the main raw material, a silane coupling agent KH550 as modifier, preparation of the silane-modified polyether type in WPU. Emulsion stability and appearance, particle size and viscosity, film and glass transition temperature, heat resistance, water absorption, water contact angle and the film mechanical properties, wettability and adhesion strength of the UHMWPE fibers. With the increase in the amount of KH550, silane-modified polyether WPU performance trend similar to the silane-modified polyester in WPU modified polyether WPU comprehensive performance superior to the polyester in WPU has more. good cold resistance, higher mechanical properties of UHMWPE fiber infiltration and bonding properties, and more suitable for UHMWPE fiber composite application.
|