The Study On The Optimization Craft Of Waterborne Polyurethane Binder For Nonwoven Fabrics As Synthetic Leather

Synthetic leather produced by sea-island bi-component fibers has become the new developing trend in synthetic leather field and it shows great developing potentialities. This paper aims to do basic research contributing to the new environmental- friend synthetic leather process through using waterborne polyurethane as the binder.The paper mainly discusses the function and influence of some main factors in the process of synthetic leather. About the process, there are two process lines, which are "alkali-dissolution first" and "alkaki-dissolution afterward".This paper also suggests the craft of alkali treating and we find main factors on the craft. Finally we make an experiment on these factors by orthogonal equation and analyze this influence of the process on all performance of products. The results are as followed:Alkali concentration , alkali treating time and temperature have great effect on its rate of weight-loss and the tensile strength.And alkali concentration,alkali treating time is more important than bath ratio.Usually, higher temperature and longer treating time result in higher rate of weight-loss.The three factors have apparent effect on weigh-loss ratio.At last we get the optimum paraments which are: bathing ratio 1:50, alkali treating temperture 95°C. alkali concentrate 16.07 g/l; alkali treating time :30mins;PVA:4.36%;PU 22.38%;Compared with "alkaki-dissolution first", "alkaki-dissolution afterward" is more appropriate on manufacture of synthetic leather and the products have higner tensile strength than the ones without alkali treatment.