Synthesis Of Thermosensitive Hydrogel And Its Application In Improving The Moisture Permeability Of Cotton Fabrics

Poly-N-isopropylacrylamide(PNIPAM)is one of the most studied thermosensitive hydrogels.Its phase transition temperature is near 30 ?,which is close to human body temperature.So it is widely used in coatings,biomedicine and Shading materials and other fields,but the application of the textile is not common.By using the phase transition process of PNIPAM,the hydrogel was used to improve the performance of cotton fabric in theory.Improving the breathability of cotton is an important means to improve the thermal comfort of the fabric,so it is a new way to develop smart textiles.This subject is to develop a new kind of finishing agent to improve the respiratory properties of cotton.PNIPAM was synthesized by using N-(NIPAM),polyether glycol,maleic anhydride and emulsifier,and then finish it to the cotton fabric.The research process is mainly divided into the following three parts:In the first part,the influence of synthetic raw materials on the stability of PNIPAM was studied through experiments.The results indicate that NIPAM was synthesized from acryloyl chloride and isopropylamine,and the structure of NIPAM could reach the desired effect;When the content of functional monomer NIPAM was 10%,the thermal stability of the synthesized PNIPAM hydrogel was good,the gel did not occur and the particle size of PNIPAM was larger;When homemade emulsifier(?)was used as the emulsifier,the stability of the synthesized thermosensitive hydrogel PNIPAM was good and no gel;The thermosensitive hydrogel PNIPAM synthesized by general small molecule crosslinking agent(such as EGDMA)has good temperature sensitivity,but the particle size is small,and the maximum temperature is only585 nm at 20 ?.In the second part,the influence of the diene cross-linking agent on the particle size of PNIPAM was investigated,and the effect of synthetic PNIPAM on cotton fabric by physical padding was studied.The results indicate that MA-PEG-MA was synthesized by the reaction of polyethylene glycol(PEG)and maleic anhydride(MA)at a molar ratio of 1:2;MA-PPG-MA was synthesized by the reaction of polypropylene glycol(PPG)and maleic anhydride(MA)at a molar ratio of 1: 2;PNIPAM was synthesized using MA-PPG-MA as a cross-linking agent,when the content of MA-PPG600-MA was 2.5%,the particle size of PNIPAM could reach 825nm;PNIPAM was synthesized using MA-PEG-MA as a cross-linking agent,when the dosage of MA-PEG600-MA was 2.5%,the particle size of PNIPAM was the largest and the swelling ratio of hydrogel was the largest;when PNIPAM was synthesized with MA-PEG600-MA as the crosslinking agent,the effect of PNIPAM on the moisture permeability and permeability of cotton fabric was the highest;when the dosage of MA-PEG600-MA was 2.5%(relative to monomer mass),PNIPAM improved the breathable effect of cotton fabric the best;when the concentration of PNIPAM finishing liquid is 100 g / L,the improvement of cotton fabric breathability is good,economic and environmental protection.In the third part,the reaction of the crosslinking monomers can be introduced into in the synthesis process PNIPAM,and PNIPAM was grafted onto the cotton fabric via a bridging agent.Then the effect of HEMA dosage on the breathability of cotton fabric was investigated,and the washing fastness of cotton fabric was tested.The results indicate that the introduction of crosslinkable reactive monomer HEMA in the synthesis of PNIPAM can synthesize hydrogels with good temperature response,and when the amount of HEMA was 0.4% of the mass of NIPAM,the synthesized PNIPAM had the largest particle size;Grafted temperature-sensitive hydrogel after the cotton fabric in the process of heating and cooling can have intelligent breathability,and HEMA dosage of 0.4%,the best results;The grafted cotton fabric was washed with water for 5 times,the weight loss was little and the grafting fastness was good.