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With the development of economy and society, raising the environmental protection, the content of VOC or HAP in polyurethane products was restricted to using in several countries. The volatilization and vestigital of solvent were harmful for constructor and consumer. The traditional solvent-borne polyurethane materials were forbidden in some industries, for example, family decoration, textiles and clothing, and so on, waterborne polyurethane, non-solvent polyurethane and polyurethane-based nanocomposite as new materials were progressively know by people.There are two categories of aliphatic and aromatic in the field of polyurethane materials at present. The polyurethane materials which are synthesized by aliphatic isocyanates show anti-yellowing and good flexibility characteristics, being poor intensity and abrasion resistance than the aromatic. The polyurethane film is superior to TDI in the strength, abrasion resistance and flexibility where the polyurethane film are synthesized by 4,4-diphenyl methane diisocyanate (MDI), which is symmetrical in structure and exhibits the large molecular weight, saturated vapor pressure, low toxicity characteristics and lower price. In addition, the polyurethane film can be dried quickly, suggesting that it has broad market prospects.In the first chapter, MDI based polyurethane materials will be used as the main line, introducing about the progress of study on the polyurethane and their functional modification with the application of waterproof and breathable textile of the coating adhesive respectively. Further, we also introduced the progress of polyurethane nanocomposites, modification mechanism and the tendency of the future development. Then we introduced the current research of MDI water-based and solvent polyurethane materials, preparation and the industrial application respectively.In the second chapter, stable waterborne polyurethane (WPU) emulsion was synthesized from MDI, polyether diol, dimethylolpropionic acid (DMPA), and so on. The properties of WPU were characterized by FT-IR, particle size analysis, tensile testing, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and water absorption test. Then the emulsion microstructure of latest and one year later was researched by transmission electron microscope (TEM). The influences of types of polyether diol, chain extenders, hydrophilic chain extenders, and cross-linkers on the mechanical property, thermodynamic property, and water resistance of the prepared WPU dispersion were discussed. From the results, it can be concluded that when use MDI,1,4-BDO,4.0 wt% DMPA as the hard segment, the WPU emulsion, which used N220 as the soft segment, has a well stability, and the film has a lot of excellent feature, such as low water absorption, big elongation at break, very soft, non-stick and fullness; which used PTMG as the soft segment, the degree of hydrogen bonding, crystallinity and heat resistance of WPU were better than others.In the third chapter, silicone was used to modify MDI based WPU, and mono-component silicone modified WPU emulsion was synthesized through graft copolymerization. The polyurethane was characterized by HNMR and IR. The results of HNMR suggested that silicone has been received on the main chain of polyurethane while the thermal analysis demonstrated that the glass transition temperature of the polymer soft segment is reduced by adding silicone and increased in the glass transition temperature of the polymer hard segment, improving the micro-phase separation which perfected the separation of soft segment and hard segment and enhancing the heat of the polymer at low temperature region. The TEM indicated that the microstructure of the emulsion would be changed by adding silicone to some extent, where silicone was comb in polyurethane chains and silicone moved to the surface with the insertion of the hydrophobic silicon. The colloidal particles didn’t transform obviously and maintained the spherical structure although the reduction of the dispersion will lead to the increase in the size of latex particle. By comparing effects that several silicone modifier acted on MDI polyurethane emulsion, other additives dubbed to water-based fabric coating adhesive were added to the polyurethane emulsion which had been synthesized and modified and then they were applied to the fabric coating, investigating the properties of waterproof and moisture penetration. The plastic coating shows the properties of both waterproof and moisture penetration which could offset effectively the insufficient of the textiles in this field.In the fourth chapter, a novel polyurethane/organic modified kaolinite nanocomposite was prepared by in-situ intercalative step-polyconsendition. First, nanokaolin as composite stuffing, which was intercalatived by oganic solvent, and then the micromolecule organic solvent was replaced by polyether to prepared polyether-nanokaolin complex, polyurethane nanocomposite was synthesized by the complex and isocyanate in the end. The modification result of nanokaolin, mechanical properties, heat resistance of nano-composite and the dispersion state of nano-filler in the composites were investigated, which was by FT-IR spectrum analysis, XRD, thermal stability, BET, SEM, tensile test, and so on. The results revealed that the intercalation rate of sonochemistry method was better, and when the content of modified nano-kaolin was 3 wt%, the composite has excellent properties. And the morphology of kaolinite was exfoliated in polyurethane matrix when the content of modified nano-kaolin was lower than 3 wt%, or else, the lamellar and agglomeration of nano-kaolin began to appear.
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