With Long Fat Side Chain Epoxy Synthesis And Its Properties

Epoxy resin(EP) for their outstanding advantages on strength, modulus and processability have been widely used in many fields. However, the application of EP such as E-51 is confined because of its low flowability and the cured resins having not enough toughness. Scientists in this field are paying great attention to the modification of EP. In this thesis, the methods of toughening EP were reviewed and the toughening mechanism was summarized, and the intramolecular plasticization of aliphatic long side chains was presented.The main routes of toughening EP domestic and overseas at present are rubber toughening, thermoplastic toughening, flexible crosslinking agent toughening and thermotropic liquid crystalline polymer toughening. These methods have some disadvantages in different aspects. EP with long aliphatic side chains were synthesized from cheap starting materials such as stearic acid, lauric acid, octylic acid. Intramolecular plasticization of EP is a new and worthy of studying route.18-pentatriacontanone, 12-tricosanone and 8-pentatriacontanone weresynthesized in high yield from stearic acid, lauric acid and octylic acid, usingMgO as catalyst. Their structures were determined by FTIR and ¹H-NMR .Bisphenols and o-methyl bisphenols were synthesized by the reaction of phenol or ortho-cresol with 18-pentatriacontanone, 12-tricosanone and 8-pentatriacoatanone respectively in high yield using HPA as catalyst. The water produced was removed by means of azeotropic distillation of toluene .The reaction was finished when the absorption peak of carbonyl group disappeared in the IR spectra . The structures of products were determined byFTIR, ¹H-NMR and ¹³C-NMR.Bisphenol diglycidy ethers (BDE) with long aliphatic side chain were synthesized by the reaction of chloropropylene oxide with 18,18-bis(p-hydroxy phenyl)-pentatriacontane, 12,12-bis(p-hydroxyphenyl)-tricosane and 8,8-bis-(p-hydroxyphenyl) -pentadecanerespectively. Their structures were assigned byFTIR. !H-NMR and 13C-NMR.Compared with titration, lH-NMR method is simpler ,accurater and faster when number-average molecular weight of BDE is determined.The viscosities of BDE with long aliphatic side chains in different temperatures were determined. The results showed that the flow activation energy of BDE were lower by 46-62% than that of E-51 EP. The DSC analysisshowed that apparent activation energy of GPD^ GTC> GPT/TETA are49.68KJ/mok 52KJ/mol and 50.52KJ/mol respectively, and the reaction orderis 0.89. The best curing parameters were determined via DSC. Tg, curing degree and tensile strength were characterized.GTC-EP was blended with E-51 EP, cured blends have also been studied and their performances were improved. The casting matrix of these blend resin hasgood compatibility ^ tensile strength n bending strength and extension ratio. Dueto the intramolecular plasticization of long aliphatic side chain, the flow activation energy of EP was decreased and the toughness of EP was improved.In this thesis, bisphenols with long aliphatic side chains and EP with long aliphatic side chains were synthesized, E51-EP were modified with EP containing long aliphatic side chains, the flow activation energy of EP was decreased and the toughness of the blends was improved.