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Adhesion promoters: Some oleochemicals can promote the adhesion of polymers to various surfaces, e.g. stearic acid can increase the adhesion of polyolef ins to metals and to the surfaces of other polymers. Erucamide is effective in the lamination of cellophane to polyethylene films, and alumina‐modified iron stearate has been found effective in aiding the adhesion of polyethylene to steel surfaces. The effect of oleamide on the adhesion of polyethylene to aluminium and to nylon 6 has been studied. Stearic acid had an adhesion promoting role in polyethylene/aluminium laminated packaging film. Barium stearate can effect the adhesiveness of poly(vinyl chloride).

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.

ICI Organics Division, PO Box 42, Blackley, Manchester M9 3DA, state that their Neramine S dyes are particularly suitable for colouring wood before varnishing, because of their intensity of colour when the powders are dissolved in methyl glycol or ethyl glycol.

“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.

Due to the environmental issues caused by petroleum lubricants used in lubrication, the concept of creating various bio-lubricants requires research globally. Thus, this study aims to develop, characterize and test the base ficus carica oil (fig oil) for its ethylene vinyl acetate copolymer (EVA) and sodium dodecylbenzene sulfonate (SDBS) content.

The sample characterization was done using the Fourier transmission infrared spectrum, whereas the morphologies of the EVA, SDBS particles and lubricated surfaces were carried out under scanning electron microscope equipment. To ensure the homogeneity of the solution (base oil and additives), the formulations were subjected to the sonication process. The anti-friction and anti-wear properties of EVA and SDBS particles as lubricant additives were investigated using a ball on a flat high-frequency reciprocating rig tribo-tester.

According to the findings, the base oil’s anti-friction and anti-wear capabilities can be greatly enhanced by the additions. revealed that the best results were obtained when 1.2% EVA + 2% SDBS was applied for the examination of wear (597.8 µm) and friction coefficient (0.106). Commercial references were used, nevertheless, and the results were excellent. This is because the particles in the contact area during lubrication have strong solubility and quickly penetrate the contact zone. The lubricating mechanisms were explained by a tribological model of the EVA + SDBS and SDBS particles.

The coefficient of friction and wear reduction caused by the use of the additives will certainly enhance system performance and protect the machine components from excessive wear that could cause damage or failure.

The originality and uniqueness of this work are officially affirmed by the authors. The authors’ autonomous and original contribution to the development of sustainable lubrication is represented in this work. To the best of the authors’ knowledge, no other study has been published or made publicly available that duplicates the precise scope and goals of our research, and this conclusion is based on a thorough literature assessment.

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.

The purpose of this paper is to investigate the effects of the components of whey‐protein based aqueous polymer‐isocyanate (API) adhesives on the bond strength.

The bond test (according to the JIS K6806‐2003 standard), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterise the whey‐protein based API adhesives with various formulations and processing technologies.

The good bond strength of the optimised whey‐protein based API adhesive was attributed to the formation of strong chemical bonds in the bondline and to the additions of polyisocyanate, polyvinyl alcohol (PVA) and nano‐CaCO₃ powder that improved adhesive cohesive strength by either chemical crosslinks or mechanical interlocking. The blending procedures of whey protein, PVA, polyvinyl acetate (PVAc) and p‐p‐MDI had great impacts on the performances of the whey‐protein based API adhesives.

SEM micrographs showed that the effects of blending processes on the bond strength, pot life and colour might be attributed to the particle size of hydrophobic p‐MDI droplet and p‐MDI distribution in the protein‐PVA matrix.

The study lays the foundations of the formulation design and the processing technology for preparing whey‐protein based API adhesives.

The effects of the components of whey‐protein based API adhesives and the effects of blending processes on the bond strength were investigated by means bond strength evaluation, FTIR and SEM analyses; whey protein is utilised successfully to prepare novel API adhesives for structural uses.

The photovoltaic modules with front glass as a protective layer are the most popular type in the industry, but for some applications it can be considered as too heavy. One of the approaches is to laminate the cells using PMMA [Poly(methyl methacrylate)] as the front layer. This polymer has good mechanical strength and optical properties but exhibits low adhesion to lamination foil. To increase adhesion between these two materials, PMMA surface treatment may be required.

To examine the PMMA treatment influence on the sample, adhesion samples’ surfaces were modified by grinding and laser cutting. Also two types of PMMA available in the market were tested, namely, smooth and satin types. The quality of lamination was determined using two methods, namely, tear test with recorded maximal tear force achieved for the samples, and environment chamber tests, in which the system resistance against the cyclic temperature variation was evaluated.

Additional treatment of the PMMA surface lead to increased adhesion of the lamination foil used. Ethylene-vinyl acetate foil in the PMMA system is sensitive to temperature variation, which can lead to system delamination, whereas polyvinyl butyral foil exhibits better environmental performance and even its adhesion to PMMA is lower.

This paper presents atypical surface modification methods that contributed to higher adhesion of lamination systems in glass-free solar modules. Glass front sheet and polymeric backsheet were replaced with PMMA. As the adhesion mechanism in the PMMA-lamination foil system differs from that in the traditional glass system, different PMMA surface treatments need to be evaluated.

The purpose of this paper is to study the recent work carried out in enhancing the properties of bitumen using nano-additives. Bitumen is a by-product obtained from the refining process of crude oil, therefore making it a diminishing product. It has been used by mankind since ages for various applications like sealants, binders, waterproof coatings and pavement construction material. It is a black viscous substance with adhesive nature.

Bitumen is used as a binding material because of its ability to become liquid when heated and become solid when cooled and thus used largely in construction of roads because of its unique properties. Low softening point of bitumen leads to melting of bitumen during summer and causes rutting of roads, whereas during winter it leads to cracking as bitumen acts brittle in nature during low temperature. Increasing global demand of bitumen has created gap between demand and supply which is increasing with the passage of time. Further modern life has created very high traffic volume and heavy load which makes it essential to improve performance of bitumen.

Research studies have reported that the thermal properties of bitumen are enhanced by using thermoplastic polymers such as styrene-butadiene-styrene, polyethylene and ethylene-vinyl acetate, rubber and bio waste etc.

This paper reviews various types of materials which have been used to improve the properties of bitumen and explores the possibility to synthesise bitumen composite materials with nanoadditives with improved structural, mechanical and thermal properties.

The purpose of this paper is to present results of the studies on modification of ethylene-vinyl acetate (EVA) encapsulation foil to be used as thermal interface material (TIM). It is estimated that poor thermal management in electronic devices can cause over 50 per cent of failures. As the junction temperature rises, the failure rate for electronics increases exponentially. To ensure sufficient heat transfer from its source, TIMs are used in various circuits. On the other hand, it is important to ensure high electric resistivity of the designed TIM.

The focus of the investigation was twofold: modification of EVA with both graphene oxide (GO) and silver nanopowder (nAg); and TIM applicability through lamination of photovoltaic cells with standard and modified EVA foil. The main problem of a new type of encapsulant is proper gas evacuation during the lamination process. For this reason, reference and modified samples were compared taking into account the percentage of gas bubbles in visible volume of laminated TIM. Finally, reference and modified TIM samples were compared using differential scanning calorimetry (DSC) and laser flash analysis (LFA) measurements.

The proper parameters of the lamination process for the modified EVA foil - with both GO and organometallic nAg particles - were selected. The nAg addition results in an increase in thermal conductivity of the proposed compositions with respect to unmodified EVA foil, which was confirmed by DSC and LFA measurements.

The experiments confirmed the potential application of both EVA foil as a matrix for TIM material and nAg with GO as an active agent. Proposed composition can bring additional support to a solar cell or other electronic components through effective heat removal, which increases its performance.