Features of the Impregnation Process and Properties of Carbon and Glass Fibre Reinforced Plastics with an Epoxy Binder

Abstract

Study of the interaction of reinforcing filler and binder at the stage of prepreg preparation, i.e. during impregnation of carbon or glass fabric by lacquer, is necessary for assessment of the distribution of its components throughout the composite and the degree of retention of the stoichiometric composition in different microvolumes of the material, for determination of features of the interaction of the binder with the filler, and, ultimately, for adjustment, where necessary, of the formulation and parameters of the production process with the aim of realising the maximum properties of the plastic produced.

Study of the Effect of Laproxides on the Physical Properties and Deformation Behaviour of Epoxy–Bisphenol a Polymers

“…Difunctional laproxide L-702 is a more effective modifier than L-301. 4. Increase in the laproxide content in the composite to 7% is not accompanied with any reduction in the softening point, which confirms the structure-forming and not plasticising (as widely assumed) action of oligoether epoxides [7].…”

“…They make it possible actively to influence the topological organisation of three-dimensional networks and accordingly the thermodeformation, inversion, and deformation and strength properties of the epoxy polymers [2]. In connection with the noted trend of practical application not only of the high elasticity effect of densely crosslinked polymers and filled matrices but also of their inversion features [3,4], it is of scientific and practical interest to investigate the effect of mono-and difunctional laproxides on the formation of the physical structure and properties of the most popular industrial polyepoxides.…”

“…They make it possible actively to influence the topological organisation of three-dimensional networks and accordingly the thermodeformation, inversion, and deformation and strength properties of the epoxy polymers [2]. In connection with the noted trend of practical application not only of the high elasticity effect of densely crosslinked polymers and filled matrices but also of their inversion features [3,4], it is of scientific and practical interest to investigate the effect of mono-and difunctional laproxides on the formation of the physical structure and properties of the most popular industrial polyepoxides.The investigation was conducted on epoxy-bisphenol A resins ED-20 and ED-16 (GOST 10587-84), and also on reactive laproxide modifiers -monofunctional laproxide 301G (TU 2226-337-10488057-97) (abbreviated below to L-301):and difunctional laproxide 702 (TU 2226-335-10488057-07) (abbreviated below to L-702):where R -m = 9-11.T h e c u r i n g a g e n t e m p l o y e d w a s isomethyltetrahydrophthalic anhydride (iso-MTHPA, acid number 665.0 15.0), and the curing accelerator was 2,4,6-tris(dimethylaminomethyl)phenol (UP 606/2).The amount of curing agent (X cur ) was determined with account taken of the content of epoxy groups in the modifier according to the empirical equation: X cur = 1.5(2605/AN)EG, g/100 g where AN is the acid number of the curing agent, and EG is the content of epoxy groups (%).Composites based on resins ED-16 and ED-20 with a content of each of the laproxides of 1, 3, 5, and 7% and a stoichiometric amount of curing agent with accelerator were prepared.…”