MODIFICATION OF OLIGOESTER MALEINATE BY ALKYL ESTER OF N-MALEINIMIDOBENZOIC ACID

Abstract

When using products from unsaturated polyester resins (NPS), often increased requirements for thermal and chemical resistance are raised. Increasing the thermal stability of the PS is possible due to the modification of resins by polymerization compounds, which can copolymerize with both oligoether maleinate and styrene. One of such effective additives is N-phenylmaleinimides. The paper presents the results of modification of unsaturated polyester grade PN-1 UT with alkyl ethers n-maleinimidobenzoic acid. The properties of terpolymers are investigated. The effect of substituents of the aromatic group with N-phenylmaleinimides on the properties of terpolymers was investigated. It is also of interest to study the effect of substituents of the aromatic group in N-phenylmaleinimide on the properties of modified polymers. It is shown that terpolymers due to their maleinimides are superior in strength and thermomechanical properties of the copolymers of oligoestermaleinate and styrene. The increase in the size of the hydrocarbon radical substituents of the aromatic group of maleinimides contributes to the increase of the thermo-and physico-mechanical properties of terpolymers. It is also shown that the glass transition temperature of polymers depends on the content of maleinimides, as well as on the structure of the aromatic group. With an increase in the content of maleinimides (up to 5 wt. %) there is an increase in the glass transition temperature and the beginning of the destructive flow. The greatest increase in glass transition temperature (30 °C) is observed at a content of 3 wt. % butyl ether of n-maleimidobenzoic acid. The increase in the length of the hydrocarbon radical (С5Н11 and С8Н17) of the ester group of n-maleimidobenzoic acid leads to the appearance of a plasticizing effect. Synthesized terpolymers can be recommended as binders in the production of heat-resistant composite materials, in particular, fiberglass.