Study On The Synthesis And Surface Physical And Chemical Properties Of Hyperbranched Polycarboxylate With Side Chains

Polycarboxylates are widely used in many fields as an environmentally friendly polyelectrolyte or surfactant. With the development of science and technology, people aren't satisfied with the traditional polycarboxylate, they need to study the polycarboxylate with the new structure. Hyperbranched polymers have many characteristics which have unique structure and the end of the introduction of many functional groups. Therefore scholars have begun to study the hyperbranched polycarboxylates.In this study, a polycarboxylate with a side chain hyperbranched structure was designed by molecular design. Compared with the traditional comb structure polycarboxylic acid, it could have higher polyoxyethylene ether side under the same anionic carboxylate density, low surface tension and higher bleed air.There are two kinds of hyperbranched polyoxyethylene ether macromonomers were synthesized. One is the two-arm hyperbranched polyoxyethylene ether monomer, which was synthesized from Ethanolamine, Aciyloyl chloride and Cl-MPEG. The other is four-arm hyperbranched polyoxyethylene ether monomer, which was synthesized from Ethanolamine, Methyl Acrylate, Ethidene Diamine, Acryloyl chloride and Cl-MPEG. And then, the hyperbranched polyoxyethylene ether macromonomer with unsaturated double bond structure was copolymerized with acrylic acid by free radical polymerization method to prepare hyperbranched polycarboxylate with side chains.The results showed that Cl-MPEG used in the synthesis of hyperbranched polyoxyethylene ether monomers is a product of nucleophilic substitution of MPEG and thionyl chloride by Nuclear Magnetic Resonance Spectroscopy and Fourier Transform Infrared Spectroscopy proved that the structure was consistent with the expectation. In addition, the synthesized G0.5 and G1 PAMAM hyperbranched molecular were match with the structure prediction through Nuclear Magnetic Resonance Spectroscopy and Fourier Transform Infrared Spectroscopy. The synthesized two-arm hyperbranched polyoxyethylene ether monomer and four-arm hyperbranched polyoxyethylene ether monomer can be found the signal peak in the Fourier Transform Infrared Spectroscopy corresponding to the expected structure.Finally, three kinds of polycarboxylate products with different molecular weights were prepared by using TPEG, two-arm hyperbranched polyoxyethylene ether monomer and four-arm hyperbranched polyoxyethylene ether monomer, and then compared the surface physical and chemical properties. The results show that when the the side chain density was increased, surface tension of the polycarboxylate aqueous solution was decreased, and the apparent viscosity was decreased,but the foaming performance had improved. The hyperbranched polycarboxylate with side chains has been put forward a new view on the molecular design and synthesis, which provides a theoretical basis for the synthesis of polycarboxylates.