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With the rapid development of automobile industry, polypropylene plastics used more and more widely. In order to broaden the scope of the use of polypropylene, to improve its competitiveness in the market, the need for surface finishing, achieve high a level of its products in appearance and performance. Through research people, polypropylene, chlorinated polypropylene (CPP), and found to have better adhesion with a polypropylene. Chlorinated polypropylene, the world demand is growing year by year, the consumption structure generally paint, adhesives accounted for 40%, the ink vehicle accounted for 40%, the other 20%. Chlorinated polypropylene small polar molecules, resulting in a low dissolving power in a polar solvent: as primer, and the lack of adhesion between the primer and topcoat layers, oil resistance, water resistance; used as a bottom surface unity paint, and commonly used in the paint resin miscibility is not good, it is difficult to complex. People do this graft modified method to adjust the molecular polarity of chlorinated polypropylene. The laboratory i.e. graft-modified chlorinated polypropylene and their modified properties were studied. Laboratory Ma Xiangdong Master with CPP (Guangdong) and maleic anhydride and the like for raw materials, grafted maleic anhydride groups, synthesized five different graft ratio of graft the CPP on the molecule. And Fan Zhong-Lei mentioned in their paper, trace hydrolyzed maleic anhydride grafted in the process of purification of the synthesized product. Firstly follow the horse in order to study the nature of the grafted product after hydrolysis, synthesis of five different graft ratio of the graft product and the recovery of acetone on the graft product was purified and dried in vacuo, its graft ratio Acidimetric , and using the IR characterization to determine the formation of maleic acid in the maleic anhydride and hydrolysis peak calculated by the relative rates of hydrolysis of the maleic anhydride grafted (hydrolyzate and does the hydrolyzate infrared area ratio) range: 50.9% to 56.1%. Because the hydrolysis rate of change of the polarity of the size will also change, so the next turbidimetric titration Determination of the solubility parameter of the five different graft product, found that the graft product is hydrolyzed after the solubility parameter becomes large, linear fitting solubility parameter grafting rate into a good linear relationship; Hansen standard five graft solubility in 27 solvents optimization calculation of the solubility parameter grafting rate its three-dimensional solubility parameter and the solubility parameter of the trace hydrolyzed graft product preliminary comparison. Finally, a thorough and systematic study of chlorinated polypropylene and its graft solution properties of the product in solution, measured at different temperatures, different concentrations of chlorinated polypropylene - toluene / tetrahydrofuran, partially hydrolyzed MAH-g-CPP - toluene / tetrahydrofuran solution properties such as density, viscosity and surface tension of the binary system, and respectively with the concentration of the relationship between the change made specific analysis. These efforts provided the basic data for the study of chlorinated polypropylene and widening the use of chlorinated polypropylene, have important academic significance and prospects for engineering applications.
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