Synthesis and Application Research of Self-crosslinking Core-shell Structure Acrylic Emulsion at Ambient Temperature
|School||South China University of Technology|
|Keywords||Acrylic emulsion Core-shell structure Self-crosslinking Boiling water resistant performance|
Polyacrylate emulsion is a class of easily prepared, performance worries Liang, a wide range of applications and comply with environmental requirements polymer emulsion. This thesis uses the core-shell emulsion polymerization process had a soft-shell structure of the hard core with a reactive ketone group self-crosslinking acrylic emulsion, the use of the reaction of the keto group with a hydrazide group, and further the room temperature curing of the film. In order to further improve the comprehensive performance of the emulsion, using multiple crosslinking system to be modified on the emulsion. Of polymerization conditions during the test, emulsifiers, cross-linking system, and crosslinking monomer, the curing conditions on the properties of emulsion. Bonded by phenolic resin treated corrugated paper successfully applied to the emulsion and the investigated polymer glass transition temperature, organosiloxane monomer types and amount of coalescent type and the amount of the emulsion adhesives resistant boiling water performance and the impact of bond strength after cooking, come to the best technology and formulations; thesis has some innovative design the structure of latex particles and emulsion cross-linking system. Synthesis test indicate that the core-shell type polymer suitable polymerization conditions: the composite amount of emulsifier is of 2 ~ 2.8wt%, and m (CO-436) ︰ m (CO-630) ︰ m (the COPS-1) = 1 - dual initiator modifier system, and the reaction of APS of 0.4wt%, the post-processing of THBP was 0.1 wt%, 1.5 ︰ 0.8 to 1 ︰ from 0.2 ~~ 0.3; the DDMs amount of 0.1 to 0.2wt%; using the first heat redox initiator SFS 0.1wt%; AA amount to 1 to 3wt%, m (GMA HEA) = 2 ~~ 3wt%; DAAm full adder in the shell, and m (DAAm) = 1.5 to 2wt%, m (ADH) / m (DAAm ) = 0.8 to 1, and the core-shell ratio of 4/6 to 6/4; resulting emulsion solids and high conversion at this time, the film a high degree of crosslinking, the polymer molecular weight distribution is wide, low water absorption, film, emulsion performance optimal. Methods such as FTIR, DSC, TEM the polymer emulsion characterized using particle size analyzer to test the latex particle size and its distribution by GPC testing of polymer molecular weight and its distribution. FTIR spectra of the ketone carbonyl group and a hydrazide group cross-linking reaction occurs to generate the hydrazone; DSC curve shows that the polymer has two distinct glass transition temperature of 18.2 ℃ and 44.5 ° C, respectively; TEM photos show a clear core-shell latex particles having The double-layered structure. The application tests showed that the use of different types of organic modified siloxane monomer emulsion adhesives can effectively improve the adhesive properties of resistance to boiling water, but the amount of C-1757 (4wt%) of Z-6040 (0.5 wt.%) of about 8 times in order to achieve the same modification effect; film-forming additive can improve the permeability of the emulsion adhesive to the substrate, thereby improving the foaming of the film after cooking; homemade emulsion market similar products Rohm Haas Company, USA developed the AC-261P acrylic emulsion performance quite, but the lower water absorption homemade emulsion film blistering less after cooking, a huge market prospect.