Epoxy/castor oil graft interpenetrating polymer networks

Abstract

Full-interpenetrating polymer networks (IPNs) were prepared from epoxy and castor oil-based polyurethane (PU), by the sequential mode of synthesis and were characterized by different techniques: swelling test, scanning electron microscopy (SEM), thermomechanical analysis (TMA), thermogravimetric analysis (TGA), tensile test, and instrumented impact test. 2,4-Toluene diisocyanate (TDI) was used as a curing agent for castor oil, at a NO/OH ratio ϭ 1.50. Diglycidyl ether of bisphenol A (DGEBA) was cured and crosslinked using 2,4,6-tris(dimethylaminomethyl)phenol (TDMP) at 1.5%, by weight, of epoxy resin. The homogeneous morphology of IPN samples of PU compositions up to 40%, by weight, revealed by SEM may be attributed to some extent to grafting of the PU phase onto the epoxy matrix, which results from the reaction between NCO groups in the PU phase with OH groups in the epoxy matrix. This has some synergistic effect on the thermal resistance and tensile properties of IPNs compared to those of the pure components, such as illustrated by the data from TGA and tensile tests. However, the grafting structure appears not to enhance their impact resistance, which probably requires the formation of rubbery particles of suitable size.

Finite Element Analysis of IPN Reinforced Woven Fabric Composite

“…Instead of giving much effort to give change in the chemistry of polymer structures, the way of mixing of one polymer alloy with another alloy shows the increase in all aspects of mechanical property. This IPN system shows excellent property than the Individual (single) components, as well the individual specific characteristics of the polymer are extracted in such a way to achieve or meet our the requirement of the present day industries [1][2][3][4].…”

Polyurethanes Based on Castor Oil: Kinetics, Chemical, Mechanical and Thermal Properties

“…Polyurethanes based on CO with different diisocyanates seem to be interesting alternatives to non-renewable-based materials, in agreement with the concept of sustainable development. There are several reports related to the elaboration of polyurethanes, such as IPNs [9,10] cast elastomers [8,11] and polyurethane coatings. [12] Different characterizations and analysis have been carried out on these systems.…”

Friction and Wear Behaviors of Two Kinds of Hydroxyl-Terminated Polydimethylsiloxane-Modified PU/EP IPN Composites Under Dry Sliding Conditions

“…A weighed amount of castor oil was placed in a roundbottomed flask, thoroughly mixed with a predetermined amount of TDI at 65°C, which corresponds to a fixed NCO/OH ratio of 1.50 [15]. The system was stirred vigorously with mechanical stirring, under an atmosphere of dry nitrogen, for about 45 min to form a PU prepolymer.…”

“…To further improve the performance of PU/EP IPNs, much attention has been paid to modifying them. Studies have shown that the PU/ EP IPN composites had rather high mechanical strength, high damping properties, and good thermal stability [14][15][16][17][18].…”