Preparation And Study Of Cross-linked PAM Solid Film

Wax deposition on oil pipelines has always been an important problem in crude oil transportation.How to effectively and low cost reduce wax deposition has always been an important research topic.Among them,the use of anti-wax film is favored by researchers,which has broad application value and development prospects.In this thesis,a cross-linked polyacrylamide solid film with swelling ability was studied,which can form a hydrophilic layer structure on the inner wall of the pipeline,thereby reducing the deposition of wax and preventing waxing of the pipeline.In this thesis,a series of cross-linked PAM solid film were prepared by polyacrylamide as raw material,and water-soluble phenolic resin PF and polyethyleneimine PEI as crosslinking agents.The effect of the ratio of PAM to crosslinking agents(mass ratio),reaction temperature,reaction time and acid-base conditions on the film formation was studied.The results showed that PAM-PF solid film with 85% crosslinking degree and100° contact angle was prepared when the ratio of PAM to PF was 2:1,reaction temperature was 50?,reaction time was 120 min under acidic catalysis.Similarly,PAM-PEI solid film with 90% crosslinking degree and 90° contact angle was prepared under the conditions of the ratio of PAM to PEI(molecular weight of 70000)of 2:1,the reaction temperature of 80?,and the reaction time of 90 min.In addition,it was found that the crosslinking degree of PAM-PF solid film can be increased to 95%after adding small molecular aldehyde,while the swelling performance of solid film was lost.However,the crosslinking degree and swelling property of PAM-PEI solid film remained unchanged after adding small molecular amine into PAM-PEI crosslinking system.The swellability analysis showed that the swelling ratio of the cross-linked PAM solid film was affected by temperature,pH and saltconcentration.The water absorption rate of the cross-linked PAM solid film was the highest in the first 15 minutes and reached the swelling equilibrium in 2 hours.Among them,the swelling ratio of the cross-linked PAM-PEI solid film can reach 431%,and the swelling ratio of the cross-linked PAM-PF solid film can reach 245%.The swollen solid film was found to have certain strength by DMA analysis.The anti-wax test of different substrates showed that the cross-linked PAM-PEI solid film coated on the epoxy resin substrate had the best anti-wax effect,and the wax deposition rate was only 1.25%.This indicated that the swelling property of the solid film was the key to anti-wax.