Development And Application Of Functional Cashmere Knitted Polyurethane Finishing Agent

The paper uses polytetrahydrofuran ether glycol(PTMG-2000),isophorone diisocyanate(IPDI),dimethylol butyric acid(DMBA),1,4-butanediol(BDO)as raw materials to synthesize water-based polyurethane(WPU)Prepolymer and modified with amino silicone oil and silane coupling agent to prepare a series of silicone modified WPU emulsions.The silicone modified WPU with excellent performance is selected to be used in the finishing of cashmere knitted products,to improve the anti-pilling and anti-felting properties of the finished fabric,and to avoid the problem of decreased hand feeling caused by WPU finishing cashmere knitted products.First,the effects of the type of polyol,the amount of DMBA and BDO,and the value of R number on the basic properties,particle size,film water absorption,and strength of the WPU emulsion,and the effect of the prepolymerization temperature on the WPU system are discussed.The results show that the WPU emulsion prepared with PTMG-2000 as the soft segment has better comprehensive performance,and the particle size and water absorption rate of the WPU emulsion prepared with the polyester 218 and polyether 310 combined polyol as the soft segment The strength is greater than the former,and the film elongation at break and heat resistance are lower than the former.During the synthesis of WPU prepolymer with PTMG-2000 as the soft segment,as the amount of DMBA increases,the centrifugal stability of WPU emulsion increases,the particle size decreases,the water absorption rate of the film increases,and the tensile strength increases first and then decreases.Small elongation at break,the optimal DMBA dosage is 5%(w / w);with the increase of BDO dosage,there is no obvious change in the centrifugal stability of WPU emulsion,the particle size increases,the water absorption rate and fracture of the film The elongation is reduced and the tensile strength is increased,and the optimal dosage of BDO is determined to be 2%(w / w);as the value of R number increases during the synthesis process,the centrifugal stability of the WPU emulsion becomes worse and the particle size increases Large,the water absorption rate and elongation at break of the film are reduced,the tensile strength is increased,and the optimal R value should be controlled at 1.6;as the prepolymerization temperature increases during synthesis,the WPU prepolymerization reaction is intense and the rate increases The doubled viscosity of the system leads to difficulty in process control.The optimized prepolymerization temperature is 80 ℃.Secondly,the effects of amino silicone oil and silane coupling agent on the performance of silicone modified WPU emulsion and film were discussed.The results show that with the increase in the amount of amino silicone oil,the centrifugal stability of WPU emulsion becomes worse,the particle size increases,the water absorption rate,tensile strength and elongation at break of the film decrease,among which block polyether amino silicone oil The 5% content modified WPU emulsion and film have the best comprehensive performance;with the increase of the amount of silane coupling agent,the centrifugal stability of the emulsion does not change significantly,the particle size increases,and the water absorption rate and fracture elongation of the film decrease,Tensile strength is increased,and WPU emulsion and film modified with 1% content of silane coupling agent KH-550 are the best in comprehensive performance.Using Fourier infrared spectrometer,thermogravimetric analyzer and other testing methods,the structure and film-forming properties of the prepared WPU were characterized and analyzed.The results show that amino silicone oil and silane coupling agent have been successfully inserted into the WPU main chain structure,and the thermal stability of the adhesive film has been improved.Finally,the self-made silicone-modified WPU emulsion with excellent performance was selected for functional finishing of cashmere knitted products,and the effects of the amount of finishing agent and finishing process on the anti-pilling and anti-felting properties of cashmere knitted products were discussed.The results show that when the amount of finishing agent is 2%(owf),the finishing temperature is 40 ℃,the finishing time is 30 min,and the finishing solution p H is 6-7,the raised pilling resistance of the cashmere knitted product can reach 4 after finishing,and the felt shrinkage Reduced to 6%-8%,feel 3-4 grade,fabric color difference before and after finishing is small,other properties are better than the finishing effect of representative finishing agent of cashmere processing enterprises.