Abstract

An acrylic resin nano-size latex whose colloidal particle size was about 20nm and solids content about 25% was prepared by a high solids content semicontinuous microemulsion copolymerization. The experimental product was employed in retanning drop [bottom] splits of pigs aiming to reinforce the leather. The offer of cross-linking agent and functional monomer were varied in the copolymerization experiment and their effect on the reinforcing function was investigated. The effect of colloidal particle size and dosage of nano-size latex on the reinforcing function also was verified.

The particle size of the latex was tested with a laser particle size analyzer, and the composition of the copolymer was analyzed by infrared spectrometry. Multifunction material test equipment was used in the physical testing of the retanned leather.

The result of the experiment showed: when the dosage of divinylbenzene (DVB) was 1.2% and the dosage of acrylic acid (AA) 0.8%, the reinforcing performance was the highest. When the colloidal particle size decreased from 64.2nm to 16.3nm, the reinforcing effect was also enhanced.

The tensile strength increased by 68%, and the tear strength improved 44% after the drop splits of pigs were retanned with 2% acrylic resin nano-size latex (with respect to the shaved wet blue weight). The effect of the dosage of sodium lauryl sulphate (SLS), n-pentanol (PA), ammonium persulfate (ASP) and AA on the colloidal particle size was also studied.