| In recent years,enlightened by bionics and guided by the concept of green economy,the preparation and application of multifunctional and green economic waterproofing agents had become a research hot spot.Two key factors were considered in the construction of waterproof layer,namely,introducing chemical groups with low surface energy,improving roughness,and realizing waterproof and oil-proof characteristics.Siloxane monomers were used to react.The obtained polymer had a cross-linked structure with Si-O-Si as the main chain.The bonding between Si-OH and cotton fibers,which contain polyhydroxyl groups,can improve its bonding degree with cotton cloth and the properties of cotton cloth.In addition,the hydrophobic barriers of-CH3,-?CH2?15CH3,-C2H4CF3 were found in the outer layer of the membrane.Modification of acrylate emulsion containing hydroxyl groups by silicone blending was used to prepare functional composite waterborne coatings.The coating was applied to coating finishing,and the properties of waterproofing,water resistance and hardness of the coating were obviously improved.Accordingly,the specific research contents and results were as follows:?1?Cetyltrimethoxysilane?HDTMS?,methyl triethoxysilane?MTES?and octamethylcyclotetrasiloxane?D4?were selected for hydrolysis polycondensation reaction,and long chain alkyl polysiloxane emulsion?LCPSO?was prepared.The structure of LCPSO was characterized by means of FT-IR which confirmed that LCPSO accords with the expected molecular design.The particle size distribution,potential value,surface morphology and roughness of LCPSO emulsion were tested by nanometer particle size and zeta potentiometer,SEM and AFM.In addition,the effects of the concentration of LCPSO solution,pH value,baking temperature and time on the application performance of LCPSO were investigated.The results showed that the zeta potential of the LCPSO emulsion was+33.9 mV,the average particle size was about 124.2 nm,the appearance was milky white and had blue light.After finishing,there was a smooth and uniform film coating on the surface of the cloth,and the roughness parameters dropped sharply.When the LCPSO concentration was 1.5%,the pH value was 7,the baking temperature was 165degrees and curing time was 3min,the textile finished by LCPSO had better comprehensive properties.It had good handle and little whiteness change.Besides,its contact angle was 142±2°and oil-proof grade was 1.?2?A novel organofluorosiloxane copolymer FCAS was synthesized with1,3,5-tri?methyl trifluoropropyl?cyclotrisiloxane?D3F?,tetramethyltetravinyl cyclotetrasiloxane(D4Vi),octamethylcyclotetrasiloxane?D4?,gamma-aminopropyl triethoxysilane?KH-550?and maleic anhydride?MAH?.It was emulsified into a milky white,blue light emulsion.The structure of FCAS was characterized by FT-IR,which proved that FCAS conformed to the expected molecular design.A new fluorosilicone waterproof and oil resistant agent FSW was prepared by blending FCAS with LCPSO emulsion.Its performance was tested and the results were as follows.The zeta potential value was+29.1 mV,the average particle size was about 120.8 nm and the appearance was milky white and blue light.The SEM displayed that there was a smooth and uniform film-like coating on the surface of the fabric after FSW finishing and the AFM test indicated that the roughness parameters of the fabric decreased significantly.The impacts of concentration of FSW finishing solution,pH value,m?LCPSO?:m?FCAS?,prebaking temperature and time,baking temperature and time on the application performance of FSW were investigated.When the concentration of FSW finishing solution was 1.5%,pH was 6.57,prebaking temperature was 140 degrees,prebaking time was 5 min,baking temperature was165 degrees and baking time was 3 min,the fabric after FSW finishing had good comprehensive properties,the water-proof and oil-proof properties of the fabric were enhanced,the hand feel was good,the whiteness changed slightly,the contact angle was 144±2°,and the oil-proof grade was 4.?3?Reference to the preparation of LCPSO,anionic long-chain alkyl polysiloxane emulsion?LAPSO?was prepared by choosing the anion nonionic emulsifier.The acrylate emulsion containing hydroxyl groups was prepared by semi continuous emulsion polymerization with butyl methacrylate?BMA?,butyl acrylate?BA?,methyl methacrylate?MMA?,styrene?St?and hydroxypropyl acrylate?HPAA?as monomers,ammonium persulfate?APS?as initiator.The structure of the emulsion was characterized by FT-IR.The results testified that PA was in line with expectations.A acrylate emulsion modified by organosilicon?LSPA?was prepared by blending LAPSO with PA emulsion.The performance of LSPA was tested and the results were as follows.The zeta potential value of LSPA was+29.1 mV,the average particle size was about 109.7 nm and the appearance was milky white and blue light.The TEM displayed that LSPA colloid particles were similar to round spherical shape,there was no apparent reunion and it had good dispersion.The instability coefficient of LSPA emulsion was 1.062,and the stability of the system was better.The LSPA coating agent was prepared by coating formulation design.The thermal stability and water resistance of the LSPA coating were characterized.In addition,the impacts of the amount of LAPSO emulsion,the ratio of soft/hard monomer,the ratio of n?NCO?/n?OH?and curing temperature on the application performance of LSPA were investigated.The results showed that the heat resistance of LSPA was good in the range of 25225?,and the contact angle of the coating was 108°.Compared with that before silicone modification,LSPA had better waterproofing property.When the LAPSO emulsion dosage was 2.5 g,the ratio of soft/hard monomer was 1:1.2,n?NCO?/n?OH?ratio was 1.2:1,curing temperature was 120?,the coating had good comprehensive properties.Its solidity was 3H,adhesion was 1st grade,impact resistance was 70cm,and its reagent resistance and water resistance were good. |
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