Air entrained collapse-preventing type polycarboxylate concrete high efficiency water reducing agent and preparation method thereof

The invention discloses an absorbing gas and keeping collapse type polycarboxylate concrete highly effective dehydragent and preparation, which comprises the following steps: (1) choosing polyalkylene glycol acrylate monomer, carboxylic monomer and allyl sulphonic acid as raw material; adding polyalkylene glycol monomer and carboxylic acid monomer into reactor incorporating condense diverting device; proceeding react; getting polyalkylene glycol acrylate monomer; (2) copolymerizing polyalkylene glycol acrylate monomer, carboxylic acid monomer and allyl sulphonic acid monomer; getting product; controlling the reacting condition with low temperature and normal pressure. When the blending quantity is 0.2% gelling material, the diminishing ratio can reach 30% and the gas content can reach 3.0-6.0%. The concrete 28d intensity can reach 130-150% and the slump of concrete nearly loss-free in 2 h, which possesses good workability without bleeding phenomenon under normal pressure.