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SYNOPSISLinseed oil was epoxidized in situ with perbenzoic or peracetic acid to produce epoxidized linseed oil (I). Effect of type and concentration of the peracid and the reaction time on the characteristics of the produced epoxidized oil were studied. Various epoxidized polyurethanes (11) with different NCO/OH ratios as well as epoxidized polyesters (111) were prepared from (I). The results obtained for the evaluation of resins (11) and (

Low molecular weight epoxy resin based on bis (4‐hydroxy phenyl) 1,1 cyclohexane was prepared and modified with various types of the prepared phenolic resins. Phenol–, cresol–, resorcinol–and salicylic acid–formaldehyde resins were used. The optimum conditions of formulation and curing process were studied to obtain modified wood adhesives characterized by high tensile shear strength values. This study indicated that the more suitable conditions are 1:2 weight ratio of phenol–or cresol–formaldehyde to epoxy resin in the presence of phthalic anhydride (20 wt%) of the resin content as a curing agent at 150°C for 80 min. Resorcinol–or salicylic acid–formaldehyde/epoxy resins formulated at 1:2 weight ratio were cured in the presence of paraformaldehyde (20 wt%) at 150°C for 60 min. The effect of the structure of phenolic resins on the tensile shear strength values of formulated resin samples, when mixed with the epoxy resins and cured under the previously mentioned optimum conditions for different times, was investigated. Metallic and glass coatings from the previous resins were also prepared and evaluated as varnishes or paints. Copyright © 1999 John Wiley & Sons, Ltd.

Blends of polypropylene (PP) and acrylonitrile butadiene rubber (NBR) were prepared with different weight compositions with a plasticorder at 180 C at a rotor speed of 60 rpm for 8 min. The physicomechanical properties and mass swell of the prepared blends were investigated with special reference to the effects of the blend ratio. The prepared epoxidized linseed oil (EL) (i.e., E 0.5 L, E 1 L, E 1.5 L, and E 2 L using 0.5, 1, 1.5, and 2 mol H 2 O 2 /mole of unsaturation in linseed oil) and maleic acid anhydride (MAH) were melt mixed in various contents (i.e., 1, 5, 10, and 15 wt %) with a PP/ NBR blend with a weight ratio of 70/30 and used as compatibilizers. The effect of the compatibilizer contents on the physicomechanical properties and mass swell of the binary blend was investigated. With an increase in the compatibilizer content up to 10 wt %, the blend showed an improvement in the physicomechanical properties and reduced mass swell in comparison with the uncompatibilized one. The addition of a compatibilizer beyond 10 wt % did not improve the blend properties any further. The efficiency of the compatibilizers (10 wt %) was also evaluated by studies of phase morphology (scanning electron microscopy). EXPERIMENTALMaterials PP (isotactic) [Moplen EP-D60R, product of Montell Polyolefins, Italy] with a melt flow index ¼ 0.35 g/ Correspondence to: E. M. Sadek (elham_sadek@hotmail. com).