Tanning properties of POSS/polymer composites containing amino and carboxyl groups

POSS/polymer composites [P(POSS-AM-MAA)] containing amino and carboxyl groups were prepared by free radical polymerization from cage-type octavinyloctasilsesquioxane (POSS-Vi), acrylamide (AM) and methacrylic acid (MAA). The structure and morphology of P(POSS-AM-MAA) were characterized by FTIR, XRD and TEM. The results showed that P(POSS-AM-MAA) was a material with a cubic cage structure of POSS surrounded by polymer chains. P(POSS-AM-MAA) combined with glutaraldehyde accounting for 4% of acid tare mass was used in the tanning process of pickled goat skin. The effects of amino content, relative molecular mass and composite material dosage on the properties of leather were investigated. The results indicated that when the amino content was 433 μmol/g, number-average relative molecular mass of P(POSS-AM-MAA) was 27237, and P(POSS-AM-MAA) dosage was 8% of the mass of pickled goat skin, combined pH was 8.5, the shrinkage temperature and thickening rate of the tanned leather were 83.7℃ and 107.3%, both higher than those of glutaraldehyde tanned leather. The free formaldehyde content in the combined tanned leather was 28.3 mg/kg. The tensile strength, elongation at break and tear strength of the combined tanned leather were 16.5 MPa, 109.5% and 58.8 N/mm, which were similar to those of glutaraldehyde tanned leather. © 2021, Editorial Office of FINE CHEMICALS. All right reserved.