Preparation of Latex Film with Macropores and Their Applications in Pigment Dyeing

Aiming at improving the permeability of the pigment dyed fabrics,two kinds of hydrophilic polyers (polyviny pyrrolidone (PVP),and polyethylene glycol (PEG) were fed into the styrene-butyl acrylate (St-BuA) copolymer latex binder respectively to prepare films with macropores. The effects of the post-added polymers on the latex film formation process and film structures were studied and the performance of the dyed fabrics wag evaluated. It was found that the drying process could still be divided into three stages even after the addition of PVP and PEG. And the water evaporation rate during the first and last stage remained the same as usual. However,after the addition of PVP,the onset of the second stage was delayed to high volume fraction,and PVP formed into spherical dispersion phase with 300 nm in diameter. It provided a great deal of interface between the latex polymer and the PVP phase,which led to an increase in the water evaporation rate during the second stage. A different case was found after the feeding of PEG. Firstly,the first stage ended at low volume fraction and a decreased evaporation rate was observed in the second stage. Secondly,the PEG dispersion appeared as fraser-like structure in the transmission electron microscopy (TEM) images with 9 μm in length. After rinsing,pores were found only in the films formerly containing PVP PEG,and the shapes and the sizes were closely correlated with the initial morphologies the PVP or PEG donains. However,the shade of color,the adrasion fastness,and the permeability of the dyed fabric were independent of the type of the post-added hydrophilic polymer.