Abstract: A tetravalent dengue inactivated vaccine is provided, including a DENV-1 inactivated antigen, a DENV-2 inactivated antigen, a DENV-3 inactivated antigen, and a DENV-4 inactivated antigen. The tetravalent dengue inactivated vaccine with a good immune effect is prepared by using four serotypes of dengue viruses as virus seeds. Furthermore, the tetravalent dengue inactivated vaccine is capable of being preserved at 4° C. for a long time, possesses lasting and effective immunogenicity, produces higher antibody titer in mice and non-human primates, has good challenge protection capability on suckling mice, has no reproductive toxicity in the mice, and has good safety.

Abstract: A tetravalent dengue inactivated vaccine is provided, including a DENV-1 inactivated antigen, a DENV-2 inactivated antigen, a DENV-3 inactivated antigen, and a DENV-4 inactivated antigen. The tetravalent dengue inactivated vaccine with a good immune effect is prepared by using four serotypes of dengue viruses as virus seeds. Furthermore, the tetravalent dengue inactivated vaccine is capable of being preserved at 4° C. for a long time, possesses lasting and effective immunogenicity, produces higher antibody titer in mice and non-human primates, has good challenge protection capability on suckling mice, has no reproductive toxicity in the mice, and has good safety.

Abstract: This invention relates to a method for preparing a star-shaped polycarboxylate superplasticizer by the first esterification step with polyol and (meth)acrylic acid as main reactants and the second polymerization step. In the first step, the star-shaped polymerizable active ends were synthesized by esterification between polyol and (meth)acrylic acid in the presence of catalyst. In the second step, the final star-shaped polycarboxylate superplasticizer was prepared by radical polymerization among the product obtained in first step, unsaturated polyoxyethylene ethers, molecular weight regulator and unsaturated carboxylic acid in the presence of initiator. The production process of this invention exhibits some characteristics including simple, easily controllable, high polymerization degree, low cost and pollution free. The star-shaped molecular structure of polycarboxylate superplasticizer can be achieved through synthesizing active “core” by esterification and “arm” by radical polymerization.

Abstract: This invention relates to a method for preparing a star-shaped polycarboxylate superplasticizer by the first esterification step with polyol and (meth)acrylic acid as main reactants and the second polymerization step. In the first step, the star-shaped polymerizable active ends were synthesized by esterification between polyol and (meth)acrylic acid in the presence of catalyst. In the second step, the final star-shaped polycarboxylate superplasticizer was prepared by radical polymerization among the product obtained in first step, unsaturated polyoxyethylene ethers, molecular weight regulator and unsaturated carboxylic acid in the presence of initiator. The production process of this invention exhibits some characteristics including simple, easily controllable, high polymerization degree, low cost and pollution free. The star-shaped molecular structure of polycarboxylate superplasticizer can be achieved through synthesizing active “core” by esterification and “arm” by radical polymerization.