High-temperature carbon fiber-reinforced plastics based on phthalonitrile resins are obtained for the first time by vacuum infusion process. For this purpose, formulations based on low-melting bis(3-(3,4-dicyanophenoxy)phenyl) phenyl phosphate monomer in combination with 1,3-bis(3,4-dicyanophenoxy)benzene and 4-[3-(prop-2-yn-1-yloxy)phenoxy]benzene-1,2-dicarbonitrile were developed. Resin viscosities η ≤ 600 mPa·s were suitable for VIP and at the same time the thermal and mechanical properties of the cured matrices were in high level featured to phthalonitriles (HDT ≥ 420℃, E ≥ 5.1 GPa). CFRP samples were manufactured by vacuum infusion process with carbon fabric and demonstrated thermal stability over 400℃ and a change of mechanical properties by less than 10% at 300℃. Present results sufficiently extend the application field of phthalonitriles as matrices for complex-shape high temperature composite parts in aerospace or high-temperature composite tooling for PEEK-like thermoplastics processing.

A new silicon-containing bicyclic monomer 5-trimethylsilylbicyclo[2.2.2]oct-2-ene has been synthesized, and its metathesis polymerization and gas transport properties of the polymer based on it have been studied. The monomer is synthesized by the two-step scheme using the Diels–Alder reaction from 1,3-cyclohexadiene and vinyltrichlorosilane followed by methylation with a Grignard reagent. The resulting 5-trimethylsilylbicyclo[ 2.2.2]oct-2-ene is inactive in metathesis homopolymerization in the presence of first- and second- generation Grubbs catalysts and a Hoveyda–Grubbs catalyst, but it slowly polymerizes when norbornene is present in the reaction mixture. The high-molecular-mass copolymer ( M w = 3.0 × 10 5 , M w / M n = 2.8) of 5-trimethylsilylbicyclo[2.2.2]oct-2-ene and norbornene possesses good film-forming properties, and its glass transition temperature is 126°C. The gas-transport properties of the copolymer have been studied.

Structural features and physicochemical properties of promising diamond-containing modifier fillers for industrial polymers, namely, detonation nanodiamonds and nanodiamond soot, are considered. Experimental results demonstrating the possibility to create prepregs with the use of the carbon fabric 1.5 К and a detonation-diamond soot-modified binder based on the epoxy-resin mixture Epikote828/Epikote154 with an anhydride-type curing agent are presented. The rheological characteristics of the diamond-sootmodified binder remain practically the same after storage for 2 or 3 days at room temperature. The dependence of the glass-transition temperatures of the binders on the content of diamond soot in the concentration range 0.025–0.1 wt % is studied, and the correlation between these results and the mechanical characteristics (breaking strength, flexural strength, and crack resistance) of the cured binders is ascertained. Within the entire range of diamond-soot concentrations, the parameters of gelation are determined and the activation energies of this process are calculated.

A new type of modified thermoset resins was synthesized by Williamson reaction from novolac resin and a mixture of allyl and propargyl chlorides of the different ratios with total allyl/propargyl substitution 50 %. The compositions of the resins were defined by nuclear magnetic resonance (1H NMR) spectroscopy, and the dependence of the cured material properties on the composition was established. An increase of a propargyl content resulted in char yield raise, and the maximum value had been found for propargylated resin which was 60 %. By differential scanning calorimetry (DSC) analysis of the curing process, it was demonstrated that exothermic enthalpy could be adjusted by varying the content of propargyl and allyl groups in the resin. It was shown that the resin substituted with allyl only ether could not be cured without decomposition, but an introduction of propargyl groups in allyl ether-modified resin allowed to obtain cured samples and thus to develop a new type of thermosetting resins.

Thermal processes of carbon fiber‐reinforced composite parts curing cycle were studied experimentally and by mathematical simulation. Flat panel, T‐stringer, and five‐stringer detail based on tetrafunctional MY721 epoxy resin were investigated. Application of standard curing cycle (heating followed by isothermal exposure at 180°C) leads to the overheating of 28°C in flat panel and of 30°C in T‐stringer of 24 mm thickness. The model considers the vacuum bag with auxiliary materials as separate layers. This approach allows to simulate the shifting of thermal field to the vacuum bag side. Simulation results show good agreement with the experimentally observed temperature fields. The model helps to optimize the curing cycle to reduce the local overheating. The same temperature regime could be used for all three geometries. Therefore, the optimization can be carried out only for the simple‐shape parts to save the calculation time and simplify experiments at the stage of model testing. POLYM. COMPOS., 37:2252–2259, 2016. © 2015 Society of Plastics Engineers

The influence of spray adhesives used in carbon fiber reinforced composite lay up process on mechanical properties and microstructure of hardened composite were investigated. It was established that residual glue in a volume of composite material results in the increase in a strength parameters at the bend of short beam from 20% and up to 10% at compression.

Polymeric matrices for composites have a number of unique properties. Their improvement is actual task for researchers. Material with required properties can be gotten by varying matrix composition and proper selection of modifier. It is known that modifier with graphite nature improves electric and thermo conductivity, but its influence on mechanical properties is unsertain. It was shown in this research that strength and fracture toughness of modified polymeric matrices become worse, but tensile and flexure elastic modulus increases. It was found that water absorption of samples increases with modifier addition without dependence of its nature and concentration

Various composition binders based on bismaleimide resins were investigated. Composition and curing mode for the infusion resin was developed. The physical and mechanical properties of the polymer matrix and composite material based on the developed bismaleimide resin were studied.

Relaxation processes, electric conductivity and dielectric permittivity in the curable compositions based on the epoxy oligomer, hardener and modifier were investigated by dielectric spectroscopy. This technique allowed to conduct real-time evaluation of conversion degree, gel and vitrification times, the beginning of phase separation in curing processes. Results of this method were proved by DSC and rheological investigations. There were measured physical and chemical parameters, as well as morphology of polymer system was studied.