Preparation And Properties Of Unsaturated Polyester Resin Based On Pipeline Repair Materials

As the medium of long-distance fluid transportation,pipeline can be found in energy mining,industrial and agricultural devices,municipal areas and so on,and plays an important role in the national economy.During the operation of the pipeline,due to earth rock pressure,corrosion of transmission medium and other factors,the pipeline will inevitably be broken,leaked and other damages,which will affect the quality of pipeline operation and need to be repaired in time.The traditional repair methods such as mechanical welding and mortar spraying need to excavate the pavement environment where the pipeline is buried.The construction links are complex and destroy the normal living order nearby,which has been gradually eliminated.The Trenchless Pipeline Repair Technology,which uses the repair hose made of pipeline repair material to fit and repair the inner wall of the damaged pipeline without excavating the road surface,is more in line with the needs of the new era.Unsaturated polyester resin plays a key role in pipeline repair materials and has important research value.This paper mainly studies the UV curing unsaturated polyester resin as the pipeline repair material suitable for uv-cipp Trenchless Pipeline repair process.Firstly,this paper evaluates and demonstrates the selection of resin raw materials,uses two-step synthesis of unsaturated polyester resin,introduces pentaerythritol Triallyl ether for end sealing for air drying modification,and uses a new cross-linking diluent ethoxylated trimethylolpropane triacrylate to confirm the effectiveness of the preparation through characterization,tests with reference to standards to test the performance,and explores the respective components and proportions of dibasic acid and dibasic alcohol,The effects of the addition amount of diluent and other factors on the physical and chemical properties of polyester cured products,and the effects of the addition amount of allyl ether,acid alcohol ratio,end capping temperature and other factors on the air drying properties.Finally,the raw materials,proportion and preparation scheme that make the comprehensive performance of unsaturated polyester resin best after curing are obtained.The first part of this paper mainly studies the preparation and performance test of a new UV curable unsaturated polyester resin.Through experiments and test verification,the effects of the composition and proportion of dibasic acid and diol,the amount of crosslinking diluent and other factors on the comprehensive properties of the resin after curing are discussed,The optimum preparation process is as follows: n(phthalic acid):n(isophthalic acid)= 1:2,n(neopentyl glycol): n(1,2-propylene glycol)= 7:3,n(saturated dibasic acid): n(unsaturated dibasic acid)= 1:1,m(polyester): m(crosslinking diluent)= 60:40.The resin paint film prepared with this ratio has a great improvement in acid,alkali,water and solvent corrosion resistance compared with the traditional resin,the volume shrinkage is as low as 6%,and the impact resistance is 16000 g.cm,flexibility 5mm,adhesion grade 0.In addition,pentaerythritol Triallyl ether was introduced to improve the air drying performance.The effects of allyl ether dosage,acid alcohol ratio and capping temperature on the air drying performance were discussed.The scheme with the best air drying performance was determined: the addition amount of allyl ether accounted for 12wt% of polyester,n(dibasic acid): n(dibasic alcohol)= 1.1:1,and the capping reaction temperature was 190 ℃.The optimum air drying performance of resin paint film: surface drying time 11 S,actual drying time 45 s.The second part of this paper focuses on the strengthening of resin properties.Firstly,the surface of the fiber was modified to improve the interfacial compatibility.The carbon fiber was modified by mild surface oxidation with 0.3w% lanthanum chloride aqueous solution and 20W% hydrogen peroxide aqueous solution,and the aramid fiber was treated by low-temperature plasma polarization.The reinforced fiber was made under the action of silane coupling agent KH570.The comprehensive performance test is carried out to test the reinforcement effect,and explore the influence of the mass ratio of modified carbon fiber and modified aramid fiber,the amount of reinforced fiber and the amount of coupling agent on the performance reinforcement effect.After comprehensive evaluation,the process scheme with the most obvious improvement effect is determined: m(modified carbon fiber): m(modified aramid fiber)= 1:2,The addition amount of reinforcing fiber is 9W% of resin and the amount of coupling agent is 12W% of resin.The resin paint film prepared after the implementation of this scheme has a considerable improvement in acid,alkali,water and solvent corrosion resistance.On the premise of maintaining flexibility and adhesion,the impact strength has been improved by more than 20%,and the improvement effect of comprehensive performance is obvious.