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文獻(xiàn)名： Use of a CO2-switchable hydrophobic associating polymer to enhance viscosity–response

 

作者： Hongsheng Lu1,2, Ya Liu1, Jifeng Jiang1 andZhiyu Huang1,2

1School of Chemistry and Chemical Engineering, Southwest Petroleum University, Xindu, Sichuan, People's Republic of China

2Engineering Research Center of Oilfield Chemistry, Ministry of Education, Xindu, Sichuan, People's Republic of China

 

摘要：A series of copolymers, poly(acrylamide)-co-poly(N,N-dimethylaminoethyl methacrylate)-co-poly(N-cetyl DMAEMA) (abbreviation PDAMCn), was synthesized with different monomer ratios. The resulting copolymer solution shows pronounced viscosity–response property which is CO2-triggered and N2-enabled. Electrical conductivity experiment shows that tertiary amine group on DMAEMA experiences a protonate and deprotonate transition upon CO2 addition and its removal. In addition, different incorporation rates of DMAEMA leads to two kinds of morphological change in the presence of CO2 and thus induces different rheological behaviors. PDAMCn incorporating longer hydrophobic monomer (C18DM) show more pronounced initial viscosity and higher critical stress required to cause network deformation, which consequently enhances the viscosity–response property of the solution. The addition of NaCl could also tune the viscosity of PDAMCn solution.

 

關(guān)鍵詞：polyelectrolytes;recycling;self-assembly;stimuli-sensitive polymers;viscosity and viscoelasticity