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An investigation has been carried out of the catalytic action of iron dipalmitate on the polymerisation of styrene, and of lauryl mercaptan and oleic acid, and polystyrene having good particle size distribution has been obtained by the polymerisation of styrene in the presence of stearic acid, which can also act as a catalyst in the bulk polymerisation of this monomer, optionally used along with styrene oxide. The fatty acid has also been employed along with diphenylamine and hydroxyacetophenone, to give catalysts systems for the polymerisation of styrene monomer, the acid ensuring brilliance in the moulded polymer. Stearoyl peroxide functions as a catalyst in the bulk polymerisation of styrene, whilst zinc stearate can work as a catalyst to the thermal degradation of polystyrene.

Discusses the use of piperylene‐styrene copolymer (PSC) for polychloroprene adhesive modification. States that PSC significantly improves modified adhesive properties ‐ bond strength, viscosity, high heat resistance, good adhesion to a variety of substrates, compatibility with other adhesive additives. Looks at the advantage of using more environmentally friendly technology for thermoplastic rubber bonding with PSC modified polychloroprene adhesives. Concludes that the new adhesive product can be used for specific combinations of materials and application methods, making it possible to produce cheaper and better products.

In surface coatings, no single resin binder possesses all the desirable properties. It is, therefore, a general practice to blend different polymers or copolymers having suitable complimentary properties in order to get the desired film characteristics provided that the blended polymers are compatible with each other. Hence, a wide range of performance characteristics can be achieved by blending.

To synthesise and characterise homo and copolymer of 4‐nonylphenyl methacrylate (NPMA) and styrene and to determine monomer reactivity ratios by the application of conventional linearisation methods such as Finemann‐Ross (F‐R) and Kelen‐Tudos (K‐T) methods.

New methacrylic monomer, NPMA with a pendant nonylphenyl group was copolymerised with styrene. All monomer and polymers (homo and copolymer) are characterised and subsequently the monomer reactivity ratio was determined.

The monomer reactivity ratios were determined by application of conventional linearisation methods such as F‐R (r₁=0.41±0.05; r₂=3.47±0.31), K‐T (r₁=0.43±0.19; r₂=3.54±0.09) methods. The thermogravimetric analysis (TGA) of the polymer in nitrogen reveals that it posses very good thermal stability in comparison to alkyl acrylates due to presence of pendant nonylphnyl group.

New methacrylic monomer, NPMA was synthesised by reacting nonylphenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a base. Copolymers of NPMA with styrene were synthesised in MEK using benzoyl peroxide (BPO) as initiator under nitrogen atmosphere at different feed composition.

The method developed is a simple and easy method of copolymerisation of styrene with methacrylate to obtain copolymer of better properties.

The method developed is a novel method for enhancing the thermal, as well as surface adhesion, properties which has several applications in surface coatings and adhesives.

Much to the relief of everyone, the general election has come and gone and with it the boring television drivel; the result a foregone conclusion. The Labour/Trade Union movement with a severe beating, the worst for half a century, a disaster they have certainly been asking for. Taking a line from the backwoods wisdom of Abraham Lincoln — “You can't fool all the people all the time!” Now, all that most people desire is not to live easy — life is never that and by the nature of things, it cannot be — but to have a reasonably settled, peaceful existence, to work out what they would consider to be their destiny; to be spared the attentions of the planners, the plotters, provocateurs, down to the wilful spoilers and wreckers. They have a right to expect Government protection. We cannot help recalling the memory of a brilliant Saturday, but one of the darkest days of the War, when the earth beneath our feet trembled at the destructive might of fleets of massive bombers overhead, the small silvery Messerschmits weaving above them. Believing all to be lost, we heaped curses on successive Governments which had wrangled over rearmament, especially the “Butter before Guns” brigade, who at the word conscription almost had apoplexy, and left its people exposed to destruction. Now, as then, the question is “Have they learned anything?” With all the countless millions Government costs, its people have the right to claim something for their money, not the least of which is the right to industrial and domestic peace.

Aluminium and zinc pigments corrode in aqueous alkaline paint media with the evolution of hydrogen. Maleic acid‐styrene‐acrylic ester copolymers were synthesized by copolymerisation of maleic acid anhydride, styrene and different (meth)acrylic esters. Three acrylic esters (ethyl, n‐butyl, n‐hexyl) and two methacrylic esters (n‐dodecyl, n‐octadecyl) were used; the copolymers with long‐chain acrylic esters are amphiphilic. Additionally, a commercial (non‐amphiphilic) styrene‐maleic acid copolymer (SMA) with similar molecular mass and acid number was tested. The corrosion reaction of aluminium and zinc pigments in aqueous alkaline media can be inhibited by addition of these copolymers. But aluminium and zinc pigments react completely differently with the examined copolymers. With addition of the amphiphilic maleic acid‐styrene‐acrylic ester copolymers to aluminium pigment dispersions the evolved hydrogen volumes decrease with increasing chain‐length of the acrylate monomer in the copolymers, whilst with zinc pigment the hydrogen volumes increase, which is just the opposite compared with aluminium. Furthermore, there exist mathematical correlations between the number of carbon atoms of the ester alcohol of the acrylate monomer in the copolymers and the hydrogen volumes evolved.

The purpose of this paper is to study the effect of monomer composition in core‐shell latex prepared from co‐polymer of styrene‐butylacrylate (BA)‐methyl methacrylate (MMA) and their paint properties.

The core‐shell latex was prepared by a stepwise semi‐batch emulsion polymerisation. A set of dispersion was made with the different core‐shell compositions. The core phase consists of a copolymer of styrene‐BA‐acrylic acid (AA) and the shell phase consists of a copolymer of MMA‐AA. The properties of latex were determined by solid content, viscosity, pH and particle size. Subsequently, emulsion paint (PVC‐37 per cent and NVM‐53 per cent) was prepared using core‐shell latex. The paint properties were determined by block resistance, gloss, elongation at break, etc. The particle morphology was characterised with transmission electron microscope (TEM).

Core‐shell structure of latex was confirmed by TEM. The performance of core‐shell latex has been optimised and the best combination achieved with 25‐40 per cent of hard phase in core‐shell latex.

Although the core‐shell structured latex was prepared from co‐polymer of styrene‐BA‐MMA monomer, the system could be extended with other monomers depending on the end use of surface coating.

The paint industry may use this method to improve paint properties.

The paper shows that, by use of core‐shell latex, it is possible to achieve high‐block resistance, hardness, elasticity and gloss.

The paper deals with using the maleinized polybutadiene as a binder in anticorrosive coating compositions. This aqueous emulsion can be as a binder mixed with the styrene–acrylate dispersion in any ratio, evaluating thus positively a series of final anticorrosive coating properties. The aqueous emulsion binder based on the maleinized polybutadiene was compared to other aqueous (alkyd, urethanized alkyd, or polyurethane) emulsions. The coatings formed by the aqueous maleinized polybutadiene emulsion and styrene–acrylate dispersion show a far higher efficiency than the coatings consisting of a styrene–acrylate dispersion alone with respect to anticorrosion protection function.

Emulsion adhesives can be subdivided on the basis of chemistry to acrylics, styrene‐butadiene latices, styrene‐butadiene/natural rubber blends, vinyl acetate copolymers and natural rubber latices. Acrylics have the advantages of being easily modified by changing the type and amount of polar comonomers. They have excellent ageing characteristics.

Details the preparation of emulsion copolymerization of styrene (St)‐vinylacetate (VAc) with different molar ratio 33:67(A1), 50:50(A2) and 67:33(A3) using redox initiator system (k2S208/NaHS03) and investigates their film forming. Finds that the drying film characterization took on a brittle property which is attributed to the nature of styrene polymers. Explains that molar ratio 67:33 from butyl acrylate (BuA‐VAc) and vinyl acetate (B1, B2 and B3) in the presence of pluronic F87 was chosen as the coemulsifier as it gives good transparent and elastic film properties but has a tacky character owing to the nature of butyl acrylate polymer. Shows that styrene‐butylacrylate (St‐BuA) 67:33 molar ratio(C) has high conversion and a solid content of 51 per cent, and its film forming gives a transparent sheet that dries within 45 minutes. Notes that incorporation of these latices into interior and exterior coatings gives good characterization (hardness, ductility, adhesion and washability of 4,042 cycles) compared with the standard specifications for evaluation of latex paint.