Preparation of self-crosslinked fluorocarbon polymer emulsion with core-shell structure by the method of soap-free emulsion polymerization

Abstract

Using methyl methacrylate (MMA), butyl acrylate(BA) and hexafluorobutyl acrylate(HFBA) as main raw materials, we prepared self-crosslinked fluorocarbon polymer emulsion with core-shell structure via soap-free emulsion polymerization when the conception of particle design and polymer morphology was adopted. Moreover, the influence of mole ratio of BA to MAA, pH value on the oligomer was studied. And the effects of the added amount of oligomer, self-crosslinked monomer and HFBA, mass ratio of BA to MMA, reaction temperature and the initiator on the polymerization technology and the performance of the product, were investigated and optimized. The structure and performance of the fluorocarbon polymer emulsion were characterized and tested with FTIR, TEM, MFT and contact angle and water absorption of the latex film. The experimental results show that the optimal conditions for preparing fluorocarbon polymer emulsion are as follows: for preparing the oligomer, mol ratio of BA to MAA is equal to 1.0: 1.60, and pH value is controlled within the range of 8.0 and 9.0; for preparing fluorocarbon polymer emulsion, the added amount of oligmer[P(BA/MANa)] is 6%; mass ratio of BA to MMA is 40: 60; the added amount of self-crosslinked monomer is 2%, the added amount of HFBA is 15%; reaction temperature is 80 °C; the mixture of potassium persulfate and sodium bisulfite is used as the initiator. The film-forming stability of the fluorocarbon polymer emulsion and the performance of the latex film, which is prepared with the soap-free emulsion polymerization, are better than that prepared with the conventional emulsion polymerization.