New polymer composites on the basis of epoxy resin and different fine dispersed mineral powders (andesite, bentonite, diatomite, liquid glass and quartz sand) were obtained and their mechanical (ultimate strength), thermal (temperature dependence of the softening) and water absorption properties were investigated. It was established that all properties of these materials were essentially improved, when the same fillers modified by tetraetoxysilane (TEOS) were used.
Crosslinking of epoxy-oligoesteric mixtures composed of ED-20 dianic epoxy resin and TGM-3 oligoesteracrylate has been studied in the presence of dioxydiphenylpropane diglycidyl ether modified with adipic acid (DCDER). Crosslinking was carried out at room temperature and while heating at 383, 403 or 423 K using polyethylene polyamine as a hardener. The procedure of DCDER synthesis has been developed. The structural changes were controlled by determining film hardness and gel-fraction content. The chemistry of films formation was confirmed by IR-spectroscopy.
A series of polymer alloys based on different compositions of Nylon 6,6 oligomers (NYL66Oґs) and epoxy resin have been prepared. The oligomer was extracted from the waste residues of the industrial production of nylon 6,6 and was dissolved in the epoxy resin. The mixture was crosslinked at 333 K using dodecenylsuccinic anhydre (DDSA) as a curing agent. The tensile strength and flexural modulus were found to increase with the addition of NYLO66O up to a maximum value of 2 wt % oligomer content.
Cardanol-based novolac-type phenolic resin was synthesized with a mole ratio 1.0:0.5 of cardanol-to-formaldehyde using a dicarboxylic acid catalyst such as succinic acid. The cardanol-based novolac-type phenolic resin may further be modified by epoxidation with epichlorohydrin excess at 393 K in a basic medium to duplicate the performance of such phenolic-type novolacs. Carboxyl-terminated butadiene acrylonitrile copolymer (CTBN) has been studied by various researches with diglycidyl ether of bisphenol-A (DEGBA) epoxy resin and epoxidized phenolic novolac resins.
New epoxy resins with fluorine atoms have been synthesized via chemical modification of dianic epoxy resin with fluorine-containing alhocols-telomers C7, C9 and C13, using benzyltriethylammonium chloride and KOH as a catalyst system. Their characteristics have been examined. The structure of synthesized products has been confirmed by IR-spectroscopy. It has been shown that new epoxy resins may be used as active plasticizers for industrial epoxy resin.
Resin derivative containing methacrylic fragment and free epoxy group at the same time has been synthesized via chemical modification of ED-24 epoxy dianic resin by methacrylic acid. The structure of the synthesized product has been confirmed by IR-spectroscopic investigations. Derivatography was used to determine the thermal stability of the synthesized compound. It has been suggested to use methacrylate derivative of ED-24 epoxy resin as a component of epoxy-oligoesteric and bitumen-polymeric mixtures.
Crosslinking of epoxy-oligomeric mixtures has been studied at room temperature and at heating to 383, 403 and 423 K for 15, 30, 45, 60 and 75 min in the presence of polyethylenepolyamine. The mixtures consist of industrial ED-20 epoxy resin, oligoesteracrylate TGM-3 and carboxy-containing derivative of ED-24 epoxy resin. The effect of mixture composition, temperature and process time on the gel-fraction content and hardness of polymeric films has been examined. Using IR-spectroscopy the chemism of network formation has been determined.
Ultimate strength, softening temperature, and water absorption of the polymer composites based on epoxy resin (type ED-20) with unmodified and/or modified by tetraethoxysilane (TEOS) minerals diatomite and andesite are described. Comparison of experimental results obtained for investigated composites shows that the ones containing modified filler have better technical parameters mentioned above than composites with unmodified filler at corresponding loading.
The possibility of epoxy resin carboxy-containing derivative (CDER) obtaining has been studied on the basis of dianic epoxy resin ED-24 and adipic acid (AA). The synthesized CDER contains epoxy and carboxy groups at the same time. Used catalysts were benzyltriethylammonium chloride (BTEACh); 1,4-diazobicyclo[2,2,2]octane; N,N-dimethylaminopyridine; 18-Crown-6, potassium hydroxide, triethylamine and 18-Crown-6+ZnCl2 catalytic system. The effect of the catalyst nature and amount, reagents ratio, process temperature and time on the reaction proceeding between ED-24 and AA has been determined.
A new oligomer with unsaturated double bonds in the side chains has been synthesized via chemical modification of polyglycidyl phenol-formaldehyde oligomers (PGPFO) by methacrylic acid (MA) using benzyltriethylammonium chloride as a catalyst. The effect of temperature and reaction time on the reaction proceeded between PGPFO and MA has been studied. The effective rate constants and activation energy of the reaction have been calculated. The structure of the synthesized oligomer has been confirmed by chemical and IR-spectroscopic analyses.