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Usually through physical or chemical modification and given its special features technical fabric or a fabric called functional fabrics. Such fabrics with high technical content, compared with the general textiles, price sensitivity is low, get higher profits. Water repellent fabrics and technical fabrics are flame retardant fabrics greatest demand, the application of the most widely used types of fabrics. With the increasingly strengthened environmental protection, green solvent-free water-dispersible fabric finishing agent development is imminent. Silicone is resistant to high temperature performance, low surface energy, physical inertia and other characteristics, the silicone-treated fabric repellency good, smooth and soft. However, silicone textile finishing agent in the presence of low adhesion with the fabric, lower mechanical strength, higher prices are not washable and inadequacies. Polyurethane has good adhesive strength, toughness and wear resistance, has been widely used as a waterproof breathable leather and fabric coating agent. Based on the characteristics of these two materials, the thesis of silicone and polyurethane copolymer, the two combine to achieve the complementary strengths of the two materials, performance adjustable. Into account environmental factors, the development of water-dispersible silicone - polyurethane block copolymer as a fabric water repellent finishing agent. The use of the fabric in the finishing process of the low surface energy silicone segments may migrate to the surface enrichment of the fabric, the fabric near the polyurethane segments through hydrogen bonding and bonding with the fabric tight, water repellent, and to achieve both the adhesive and the fabric sex with better aim. Using the hydroxy-terminated polydimethylsiloxane (PDMS) with aminopropyl methyl dimethoxy silane (DB-912) prepared by the reaction of ammonia end of a series of different molecular weight hydrocarbyl polydimethylsiloxane oligomer (NS) as a chain extender, thereby preparing a water dispersion of silicone - polyurethane block copolymer (WPSUR). The type of the hydrophilic agent, a carboxyl group content, dihydroxy polyether type, the amount of castor oil, chain extender type, NS molecular weight silicone content, solids content of the aqueous dispersion and the dispersion WPSUR size, stability and rheology characteristic relationship between film investigated its WPSUR absorbent material, the contact angle with water, mechanical properties, heat stability, adhesion to the fabric and the water repellency of the treated fabric, resistant to hydrostatic pressure and washable and other characteristics. This selection of the hydrophilic agent, there are two: one is a glycerol and glycerol prepared by reacting maleic anhydride half ester (GSE), the other one is dimethylolpropionic acid (DMPA). Half esters of glycerol obtained from the parents agent an aqueous dispersion of low price, film-forming material is soft, but the carboxyl content required to achieve more than 2.5wt% water in order to obtain a stable dispersion; while the use of a hydrophilic agent DMPA, carboxy when the content is higher than 1.6wt%, can be obtained a stable aqueous dispersion. Trihydroxy use containing aliphatic hydrocarbons and long-chain triglyceride of castor oil as a raw material in the internal crosslinking introduced into the system in order to improve mechanical properties and water repellency properties. NS-linking agents used for the expansion of the obtained fat WPSUR with a diamine, a silane coupling agent of low molecular weight hydrocarbon WPU ammonia compared to the film greatly improved water resistance, and the surface of the water contact angle above 100 °, the heat resistance and mechanical strength are improved. DB-912 using PDMS, prepared by the reaction of the silicone side chains contain long-chain amino alkyl side chains of polydimethylsiloxane oligomer (S 3 N 2 ) as a chain extender, the system can further improve the content of polysiloxane segments, to improve the water repellency of the film and to improve the texture of the finishing agent. The results show that when the NS and S 3 N 2 ratio of 75:25, a silicone content of 30wt%, castor oil content is 15wt%, a carboxyl group content of 1 .8 wt%, solid content of 30wt%, the prepared WPSUR the best overall performance. After the water-repellent polyester fabric finishing WPSUR, hydrostatic pressure up to 41KPa, wet after washing water repellent grade and were graded 3, and fabric adhesive strength of up 7.0N/cm, stretch film strength of 5.2 MPa, brittle transition temperature as low as -30 ℃. Indicates that the water-repellent finishing agent stability, performance, and has good application prospects. The innovation of this work are: use of hydrocarbyl-terminated polysiloxane oligomer ammonia instead of the conventional low molecular weight aliphatic diamines and amino alkyl silane coupling agent as a chain extender, the synthesis of the molecular chain organosiloxane WPSUR chain segment content increased significantly, improved water repellency of the film properties and heat stability. Castor oil as a raw material used in the introduction WPSUR internal cross-linking molecule and the hydrophobic fatty chain length, to further improve the water resistance. The use of organic montmorillonite (MMT) insulation, flame retardant toughening and prepared exfoliated WPSUR / MMT nanocomposites. The introduction of MMT, significantly improved WPSUR film surface hydrophobicity, mechanical properties and heat stability. When the MMT content of 1wt% when, WPSUR / MMT composite tensile strength and elongation at break compared WPSUR increased by 22.8% and 9.6%, reaching to both strengthen and toughening effect; their resistance Heat is also improved, compared PU, the thermal decomposition peak temperature of loss improved second 20 ℃. In this paper, the molecular chain containing phosphorus as the raw polyol, castor oil as the internal crosslinking agent, NS connected to expansion, synthesis of phosphorus, nitrogen, silicon synergistic flame retardant silicone dispersion type water - polyurethane block Copolymer (P-WPSUR). The P-WPSUR is a set of acid source, carbon and foam from a \The effects of phosphorus and silicon content of the aqueous dispersion stability, rheological properties, film, adhesion to the fabric, fabric after finishing the limiting oxygen index (LOI), the vertical burning tear length, continued burning and smoldering, washable, heat stability, char yield and carbon residue after burning microscopic morphological changes and other effects. The results show that the phosphorus content increased silicon content compared to more effectively improve the flame retardant cotton fabric. Thermogravimetric analysis (TGA) results show that both in the air or a nitrogen atmosphere, P-WPSUR have good thermal stability and excellent charring ability. P-WPSUR finished cotton fabrics can significantly reduce the mass loss rate, and make the material LOI increased dramatically. The phosphorus content of 7.1 wt%, silicone content of 20wt% of the P-WPSUR cotton fabric after finishing the best overall performance. After the P-WPSUR finished cotton fabrics, vertical burning tear length <100 mm, no smoldering, no continued burning, no melting, dripping; through eight household cleaning. After drying cycle length vertical burning tear <130mm. Composite fire retardant finished cotton fabric before washing oxygen index of 34, after washing 10 times the oxygen index of 30. Preparation of the emulsion film tensile strength 4.2 MPa, low brittle temperature -30 ℃; adhesive strength with the fabric (T-type peeling test) of up to 11.1N/cm, the fabric has good adhesion , washable good. And the film and the surface of the water contact angle of> 100 °, indicating that the treatment, the fabric finishing agent not only has good flame resistance, but also has a waterproof, good slip properties, a good application prospect.
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