Study On Emulsion Copolymerizasion Of Organosilicone Modified Acrylates Using For Building Coatings

Organic polysiloxane, with the molecular main chain of organic polysiloxane of Si-O-Si, carries dual properties of both organic polymer and inorganic compound, which includes excellent climate resistance and light-penetrating ability, good hydrophobicity and breathability, anti-stain property and abrasion resistance. As a raw material, acrylate emulsion is easily available with low price and excellent features of good film property as well as high intensity and adhesive property. With silicone-acrylate modification through emulsion polymerization techniques, the latex coating with high performances is produced with silicon-acrylic property.This dissertation makes generalized introduction of the synthesized method of unsaturated organic polysiloxane as well as the performance indicators when used as a modifier and develops a detailed literature review on silicone-acrylate soap and soap-free emulsion polymerization technique and methods for producing architecture exterior wall paint. The methods of main body ring-opening and emulsion ring-opening are adopted in producing linear unsaturated organic polysiloxane while the emulsion copolymerization techniques leads to the realization of silicone-acrylate modification. Then the following silicone-acrylate emulsions are produced: the core-shell silicone-acrylate soap emulsion with specified organic polysiloxane of Si-O-Si and three of silicone-acrylate soap-free emulsion with NaUA,NaSS/HEMA and P(BA/AA) oligomer. Based on synthetic resin emulsion performance indicators and the standard of synthetic resin emulsion paint for exterior wall, the performances of silicone-acrylate emulsion and latex coatings are inspected. The core-shell silicone-acrylate soap emulsion is illustrated by TEM and infrared spectroscopy. And the fluorescence probe techniques are employed to identify the micelle formation ability of self-made P(BA/AA) in dilute aqueous solutions.The study shows that with the emulsion ring-opening technique of producing unsaturated organic polysiloxane as the modifier and the redox initiating system as well as seed emulsion feeding method adopted, the silicone-acrylate emulsion is polymerized under the copolymerization temperature of 60～65℃and the reaction time period of 3.5～4h according to the following rations: negative ion emulsifier to non-ion as 3:2 with an amount of 3～4%,redox initiators as 3:2 with an amount of 2%,soft acrylate monomer to hard acrylate one as 3:2 with a silicon content of 10%.