A. F. Shaaban

Organotin polymers—XVI. Synthesis of p-acryloyloxybenzoic acid and n-methacryloyloxytetrabromophthalimide and copolymerizations with tri-n-butyltin acrylate and methacrylate

Abstract p -Acryloyloxybenzoic acid (ABA) and N -methacryloyloxytetrabromophthalimide (NMTP) were prepared. The monomer reactivity ratios for the copolymerization of tri-n-butyltin acrylate (monomer-1) with ABA and NMTP have been found to be r 1 , = 1.01, r 2 = 0.40 and r 1 , = 0.69, r 2 = 0.90 respectively; those for tri-n-butyltin methacrylate (monomer-l) with ABA and NMTP were r 1 = 2.21, r 2 = 0.87 and r 1 = 0.85, r 2 = 1.35 respectively. Copolymerizations were carried out in solution at 70° using 1 mol% azobisisobutyronitrile as initiator. The structures of the monomers were investigated by i.r. and 1 H-NMR.

Organotin polymers: 10. Copolymerization parameters for di-(tri-n-butyltin) itaconate with methyl acrylate, ethyl acrylate, N-vinyl pyrrolidone and acrylonitrile

The monomer reactivity ratios for the copolymerization of di-(tri-n-butyltin) itaconate (M1) with methyl acrylate (M2), ethyl acrylate (M2), N-vinyl pyrrolidone (M2) and acrylonitrile (M2) were found to be r1 = 0.387, r2 = 0.671; r1 = 0.555, r2 = 0.958; r1 = 0.033, r2 = 0.185 and r1 = 0.441, r2 = 0.425, respectively. Copolymerization reactions were carried out in solution at 60°C using 1 mol% AIBN, with copolymer compositions being determined by tin analysis. The Q and e values for di-(tri-n-butyltin) itaconate were calculated from the monomer reactivity ratios determined in the present and previous studies. The sequence distribution of the triad fractions for the systems studied were calculated at azeotropic compositions.

Improvement of white pinewood properties by impregnation with thiourea–formaldehyde resin and orthophosphoric acid

White pinewood was impregnated with thiourea–formaldehyde (TUF) resin and orthophosphoric acid (OPA) as a crosslinking agent. The best weight gains (55–138%) were obtained after impregnation with an aqueous solution of TUF resin for 1 h and impregnation with aqueous solutions of OPA at different concentrations for 1 h. Water uptake of treated wood was found to be 23% after a water-soaking test of 168 h, and a maximum antiswell efficiency was found to be 18% for a 85% OPA solution. Compression strength of the treated wood also improved with the highest value 62 KN/m2 for wood treated with a 70% OPA solution versus a value of 40 KN/m2 for untreated samples. Fire retardancy of the treated wood samples was also improved based on concentration of OPA.

Synthesis and surface activity of self‐sequestering surfactants

A novel two series of self‐sequestering surfactants have been prepared by the reaction of itaconic acid, phthalic anhydride, citric acid with oxypropylated 1,4‐butane diol and oxypropylated 1,6‐hexane diol. The structure features of these surfactants have been confirmed by IR and 1H NMR spectra. These surfactants exhibit excellent properties of self‐sequestering. Besides good surface active properties including surface tension, interfacial tension, low foaming, good wetting properties, good stability towards acidic and basic media, emulsifying power and dispresent properties, solubilization properties and good biodegradability, they possess autonomous sequestering ability without any help of additional sequestering agent.

Improvement of white pine wood properties by impregnation with mixtures of methyl methacrylate and phthalimide monomers, subsequent in situ copolymerization

White pine wood was impregnated with a mixture of methyl methacrylate (MMA) and N‐methacryloyloxyphthalimide and by other three mixtures prepared by mixing MMA and N‐methacryloyloxytetrabromo‐phthalimide. Water uptake of treated wood was found to be 54 per cent after water‐soaking test of 168 h and maximum antiswell efficiency was found to be 48 per cent for treated wood samples with non‐brominated comonomer mixture.