Search results

1 – 10 of 617
Article
Publication date: 20 October 2021

Walid S. Abdel-Wakil, Tarek M. Salama, Elbadawy A. Kamoun, Farag Abd El Hai Ahmed, Wassem Hassan, Yaser A. El-Badry and Alaa Fahmy

This paper aims to synthesize new terpolymers by the emulsion polymerization technique composed of acrylamide-based polyurethane monomers (TPM and MPM) with different vinyl acetate

Abstract

Purpose

This paper aims to synthesize new terpolymers by the emulsion polymerization technique composed of acrylamide-based polyurethane monomers (TPM and MPM) with different vinyl acetate copolymer systems, such as vinyl acetate/butyl acrylate (VAc/BA), vinyl acetate/ethylhexyl acrylate (VAc/2-EHA) and vinyl acetate/vinyl ester of versatic acid (VAc/VEOVA 10) systems. The performance of the prepared terpolymers as binders in emulsion coatings and textile industries was investigated and compared with the analogous commercial ones.

Design/methodology/approach

New waterborne polyurethane-vinyl ester-vinyl acetate terpolymers with high solid content and nano-scale emulsions have been successfully synthesized in two steps. The polyurethane oligomers were prepared by the prepolymer method as the first step. The second step involved polymerization with different vinyl monomers. The synthesized terpolymers were characterized using FTIR, scanning electron microscope, thermogravimetric analysis, minimum film forming temperature and particle size analyzer methods.

Findings

The synthesized emulsion terpolymers have shown small particle sizes averaged of 70 nm and a narrow distribution range, along with good mechanical, thermal and chemical stabilities. The surface coating layers of the terpolymers also have some important in terms of smoothness, clarity and binding ability in water-based coating for up to 4425 scrub cycles at 30 GU. Further, a high potential application textile printing was achieved at high solid content of 47–50%.

Originality/value

The effects of different isocyanates and vinyl monomers on the properties of obtained emulsion coatings have been studied. The improvement consequences of the coating evaluation of the waterborne binders for emulsion paints have been described. The properties of polyester/cotton fabric print pigment printing of textiles appear to be most promising enhancements by using the prepared nanocomposites of PU-co-vinyl acetate-co-vinyl ester as waterborne binders. So that the prepared emulsions have the potential to replace solvent-based coatings as waterborne binders for both emulsion coating and textile printing applications.

Details

Pigment & Resin Technology, vol. 52 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 1975

“Pressure polymers” is a convenient short name for vinyl acetate‐ethylene, and vinyl acetate‐ethylene‐vinyl chloride copolymers; the use of ethylene in particular necessitates…

Abstract

“Pressure polymers” is a convenient short name for vinyl acetate‐ethylene, and vinyl acetate‐ethylene‐vinyl chloride copolymers; the use of ethylene in particular necessitates operating the polymerisation reaction at appreciable pressures, in some cases up to 200 atm. However, the use of pressure in emulsion polymerisation is not an end in itself, interesting though the chemical and engineering challenge has proved to be: the development has arisen from the search for paint media with the best balance of cost and efficiency. Our first experimental vinyl acetate‐ethylene emulsions were shown at the 1966 OCCA Technical Exhibition; one of these grades has been in use on a limited scale for some years, and is now in bulk production at our Warrington factory, which began operating in October 1974. We subsequently undertook work on copolymers and terpolymers involving vinyl chloride, and bulk production of selected products has now started at Warrington.

Details

Pigment & Resin Technology, vol. 4 no. 9
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 April 2002

Lijun Qiao, Phil K. Coveny and Allan J. Easteal

Modifications of poly(vinyl alcohol) (PVA) can improve the properties and performance of poly(vinyl acetate) (PVAc) emulsions stabilized with these modified colloids. Water…

1257

Abstract

Modifications of poly(vinyl alcohol) (PVA) can improve the properties and performance of poly(vinyl acetate) (PVAc) emulsions stabilized with these modified colloids. Water resistance and toughness of the emulsions as wood adhesives can be achieved through chemical reactions of the hydroxy groups of the colloid with various modifiers. The chemical changes can be carried out either in the preparation of PVA through hydrolysis of copolymers of vinyl acetate and other monomers, or by the reaction of modifiers with PVA aqueous solutions. The modified PVAc emulsions show better properties than those of the conventional emulsions in performance tests and applications. The modified colloids are becoming increasingly used in the manufacture of PVAc emulsions in the adhesive industry, because of their advantages over emulsions made using conventional (unmodified) PVA. The trend of current research is to introduce more functionality into the colloid, so that the traditional protective colloids can be modified to function as crosslinkers and chain transfer agents.

Details

Pigment & Resin Technology, vol. 31 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 10 August 2015

Nehal S. Ahmed, Amal M. Nassar and Rabab M. Nasser

– The purpose of this paper is to prepare novel types of copolymers and terpolymers depending on jojoba, and using them as additives for lubricating oil.

Abstract

Purpose

The purpose of this paper is to prepare novel types of copolymers and terpolymers depending on jojoba, and using them as additives for lubricating oil.

Design/methodology/approach

Copolymerization of 1 mole of jojoba with 2 moles of vinyl acetate and copolymerization of 1 mole of jojoba with 2 moles of vinyl pyrrolidone were carried out. Then, two series of terpolymers were prepared by reacting (jojoba: vinyl acetate: alkylacrylate) and (jojoba: vinyl pyrrolidone: alkylacrylate), using free radical chain addition polymerization. Elucidation of the prepared polymers was carried out by using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance and gel permeation chromatography, for determination of weight average molecular weight. The thermal stability of the prepared polymers was determined. The prepared polymers were evaluated as viscosity index improvers and pour point depressants for lubricating oil.

Findings

It was found that the viscosity index increases with increasing the alkyl chain length of alkylacrylate. The effect of the monomer type was studied, and it was found that the polymers depending on vinyl acetate have great effect as viscosity index improvers and pour point depressants for lubricating oil.

Originality/value

The polymerization of jojoba as different copolymers and terpolymers was carried out. The great influence of the prepared additives on modification of the viscosity properties and pour point of the oil was observed.

Article
Publication date: 1 March 1982

Vinyl Products Ltd. (a wholly‐owned subsidiary of Unilever PLC) last month commissioned Europe's largest pressure polymerisation reactor for the manufacture of vinyl acetate

Abstract

Vinyl Products Ltd. (a wholly‐owned subsidiary of Unilever PLC) last month commissioned Europe's largest pressure polymerisation reactor for the manufacture of vinyl acetate‐ethylene and vinyl acetatevinyl chloride‐ethylene copolymer emulsions at its Warrington factory.

Details

Pigment & Resin Technology, vol. 11 no. 3
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 June 2000

Lijun Qiao, Allan J. Easteal, Clive J. Bolt, Philip K. Coveny and Robert A. Franich

Four different approaches were taken to improve the water resistance of poly(vinyl acetate) (PVAc) emulsion adhesives. The improved wood adhesives were tested according to the ISO…

1538

Abstract

Four different approaches were taken to improve the water resistance of poly(vinyl acetate) (PVAc) emulsion adhesives. The improved wood adhesives were tested according to the ISO 9020 standard. Tensile storage modulus (E’) and glass transition temperature of the polymer films were measured using dynamic mechanical thermal analysis to quantify the influence of different approaches on those variables. Gel fraction and swelling ratio of the polymer film were measured to evaluate internal crosslink density. The experimental results showed that blending melamine/urea/formaldehyde (MUF) resin with PVAc emulsions modified the water resistance considerably and the film had a high E’ since an interpenetrating network‐type structure was formed in the polymer. The advantages and limitations of each modification were assessed on the basis of comparison of the results.

Details

Pigment & Resin Technology, vol. 29 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 August 2000

Lijun Qiao, Allan J. Easteal, Clive J. Bolt, Philip K. Coveny and Robert A. Franich

Poly (vinyl acetate)‐based emulsion polymer/isocyanates (EPI) structural wood adhesives were prepared and their performance benchmark tested according to the specifications of the…

Abstract

Poly (vinyl acetate)‐based emulsion polymer/isocyanates (EPI) structural wood adhesives were prepared and their performance benchmark tested according to the specifications of the Japanese JAS‐111 standard. The changes of the glass transition temperature of the cured emulsions relative to unmodified poly(vinyl acetate) emulsion, measured using differential scanning calorimetry, indicated the chemical structure changes resulting from modification of poly(vinyl acetate) emulsion. The EPI adhesives showed excellent water resistance and near‐colourless gluelines in wood joints, ease of application and additional significant advantages over other types of wood adhesives. The performance test results are interpreted on the basis of the viscoelastic behaviour of free‐standing adhesive films. Other types of crosslinkers were used in the study to compare with the isocyanate hardeners.

Details

Pigment & Resin Technology, vol. 29 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 June 1992

Edgar S. Lower

Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer…

Abstract

Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer electrolytes. Molten palmitic acid will serve as a solvent in which to polymerise acrylic compounds, and benzyl butyrate has been examined as a solvent in which to polymerise benzyl methacrylate. Ethyl palmitate has been applied to aid the reduction of the carbon tetrachloride content of solutions of chlorinated polyisoprene, when this is removed from the polymer by steam or hot water.

Details

Pigment & Resin Technology, vol. 21 no. 6
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 November 1979

R.A. Ellis

(b) Linear Homopolymers Linear poly(vinyl acetate) and polybutadiene samples were studied by Park and Graessley using GPC combined with capillary viscometry which provided both…

Abstract

(b) Linear Homopolymers Linear poly(vinyl acetate) and polybutadiene samples were studied by Park and Graessley using GPC combined with capillary viscometry which provided both the distribution of hydrodynamic volumes and intrinsic viscosities of the samples. Their equipment comprised a Waters Associates Chromatograph (model 200) fitted with five Styragel columns of porosities 106, 105, 1.5 × 104, 104 and 3 and 103 mm eluted with THF at room temperature at a flow rate of 1 cm3 min−1. Samples of 2 cm3 nominal volume were injected at a concentration of 0.25 g per 100 cm3 and detection was by a differential refractometer coupled to a digital curve translator so that readings were digitised and fed to a teletype machine at one minute intervals. From the refractometer, the sample passed via a syphon device into an all glass viscometer of the Ubbelohde type and the whole of this equipment was totally immersed in a water bath whose volume was sufficient to smooth out minor temperature variations in the equipment. The viscometer discharge was detected photoelectrically and the time taken determined by an electronic timer which gave a signal that was also recorded on the teletype.

Details

Pigment & Resin Technology, vol. 8 no. 11
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 January 1973

Shell Research Laboratories

A relatively new concept which is now playing a major role in the studies of organic surfaces is the characterisation of such surfaces by the measurement of critical surface…

Abstract

A relatively new concept which is now playing a major role in the studies of organic surfaces is the characterisation of such surfaces by the measurement of critical surface tension, γc. The value of this property allows certain predictions to be made as to whether or not a given liquid will wet and spread on a particular solid surface.

Details

Pigment & Resin Technology, vol. 2 no. 1
Type: Research Article
ISSN: 0369-9420

1 – 10 of 617