Abstract
For graft polymerisation of styrene onto wool fibre imbibing solutions of various catalysts, among various methods known for emulsion polymerisation, the redox method is found to be most effective (NaHSO3-H2O2).
It has been supposed that the chemical groups of wool fiber which lead to graft copolymerisation are a consequence of the covalent sulfur bonds present in the wool molecule, but according to the IR spectroscopic research, it was supposed the graft copolymerisation of styrene onto the wool molecule originate from the results of the formation of radicals of structure R-NH, derived from initiator attack at the free amino groups in the presence of the NaHSO3-H2O2 redox system.
The reaction rate of grafting was given by following eouation: dθ/dt=K(100-θ) where θ is the efficiency of grafting, K the reaction rate of grafting, t the time. The activation energy of grafting calculated from the relation between In K and 1/T from Arrhenius equation was 25.2Kcal/mol.
The molecular weight of the grafted polystyren is in the order of 105_??_106 and the mechanical properties (Tensile strength, Elongation, Young's modulus) of styrene grafted wool decreases beyond 100% degree of grafting. The effect of heat setting on the styrene grafted wool fabrics were examined. The degree of grafting of about 30_??_50% were the most effective and above this point these effects decrease.
