Research On Anti-sulfur Finishing Technology And Mechanical Property Of Nylon Hook And Loop Fastener

In this thesis, anti-sulfur dig finishing and coating finishing technology of a white PA hookand loop fastener are researched. The optimum anti-sulfur finishing technological parameters ofthe fastener are gotten through a single factor experiment and orthogonal experiment. The resultshows that the effect of anti-sulfur is good and stable. Two mechanical model of the fastener’s peeland shear strength based on Djudovic and Mikhailov’s knitted loop intermesh model are set up. Atheoretical calculation formula of the peel and shear strength are deduced by mechanical analysisand figures calculation.By study of the anti-sulfur finish, a whitening technology of the fastener is gotten as followsas: the dosage of fluorescent brightener7%, the concentration of anti-sulfur fixing agent16g/L,the concentration of acid brilliant blue dye0.01g/L, the dipping temperature from40℃to100℃,the rate of temperature increase2℃/min, continuing to whiten1.5hours after the temperaturereaching to100℃. Then taking out the fastener, washing, dehydrating, drying.By study of the anti-sulfur finish,, the optimum technology of anti-sulfur is gotten as followsas: the concentration of antioxidant agent NY20g/L, the digging temperature50℃, finishingliquor pH5.2, the digging time7hours.The anti-sulfur grades of the loop fastener and hook fastener according to the nationalstandard are all4.5~5after finished by the optimum technology. When the weight of releasing SO2of rubber block is increased to150%, the anti-sulfur grades are still4~4.5. This indicates that theanti-sulfur stability of the fastener is improved remarkably after finished by the optimumtechnology.By study of the anti-sulfur coating finish, the optimum coating finish technology are gotten asfollows as: the dosage of anti-yellowing resin170%, the dosage of anti-yellowing bridging agent40%, the dosage of anti-oxidant NY4%. The anti-sulfur grade of the fastener4.5~5after finishedby the optimum coating finish technology. A mechanical model of fastener’s peel strength is set up base on Djudovic and Mikhailov’sknitted loop intermesh model. Firstly the theoretical calculation formula of single-hook peelstrength is deduced by it. Combing the hooking rate and the density of hook with it, as well as atheoretical calculation formula of the peel strength is deduced. Then the final formula is obtainedafter the peel strength is actual measured and amended. It can be used to predict and calculate thepeel strength, the deviation percentage is only less than3%.A mechanical model of fastener’s shear strength base on Djudovic and Mikhailov’s knittedloop intermesh model is set up. Firstly the theoretical calculation formula of single-hook shearstrength is deduced. Considering the hooking rate and the density of hook, the theoreticalcalculation formula of shear strength is deduced. Then the final formula is gotten after the shearstrength is actual measured and amended. It can be used to predict and calculate the shear strength,the deviation percentage is only less than2%.