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This paper aims to investigate the effects on coatings performance in the epoxy silicone resin system owing to the existence of the different chain length of open-chain epoxy monomer. In this paper, [4-Methylphenyl-(4–(2-methylpropyl) phenyl)]iodonium as photoinitiator was added into epoxy silicone resin by ultraviolet (UV)-cured polymerization to investigate the effects on coatings performance owing to the existence of the different chain length of open-chain epoxy monomer.

A simple hydrosilylation reaction was used to synthesize epoxy-based silicone prepolymers by using hydrogen-terminated polydimethylsiloxane, 1,2-epoxy-5-hexene, 1,2-epoxy-7-octene and 1,2-epoxy-9-decene as precursors.

The results revealed that the glass transition temperatures (Tg) and hydrophobicity increased with the chain length of open-chain epoxy monomer in the UV curable epoxy-based silicone coatings, and these films had excellent heat resistance, hydrophobicity, antigraffiti and ink removal properties.

The cationic photocuring systems are not susceptible to the effect of oxygen inhibition. However, the limitation of cationic light curing process is that it requires a long curing time.

The coatings prepared via the UV curing approach can provide superior antismudge effects, and thus they are promising candidates for use in various industries, especially in fields such as antismudge coatings and antigraffiti coatings.

The purpose of this study is to synthesize a new kind of a cationic-type UV-curing prepolymer diepoxycyclohexylethyl tetramethyldisiloxane, which is used to replace the current prepolymers’ common cycloaliphatic epoxy resins to prepare a novel 3D printing stereolithography material.

Diepoxycyclohexylethyl tetramethyldisiloxane was characterized and analyzed by FT-IR and 1HMR. Diepoxycyclohexylethyl tetramethyldisiloxane was compounded with a polycaprolactone polyol, some acrylates and photoinitiators to prepare a novel 3D printing stereolithography resin (3DPSLR11). Optical properties of 3DPSLR11 were investigated by HRPL-150A stereolithography apparatus and INITELLI-RAY400 UV-curing system. Tensile mechanical properties of printed 3DPSLR11 specimens were tested by WDW-50-type universal testing machine, and the glass transition temperature (Tg) was determined by DMA. Rectangle plates and double-cantilever parts were fabricated by using the stereolithography apparatus with 3DPSLR11 as the printing material, and the dimension shrinkage factors and the curl factors of the parts were investigated.

The experimental results showed that the critical exposure (Ec) of the 3D printing 3DPSLR11 was 11.6 mJ/cm², its penetration depth (Dp) was 0.18 mm, the tensile strength of the cured 3DPSLR11 was 40.1 MPa, the tensile modulus was 1,741.4 MPa, the elongation at break was 15.3%, Tg was 113°C, the dimension shrinkage factor was less than 0.85% and the curl factor was less than 8.00%.

In this work, a novel 3D printing 3DPSLR11 was prepared with diepoxycyclohexylethyl tetramethyldisiloxane as a main prepolymer. The novel 3DPSLR11 possessed excellent photosensitivity, and its cured products had good mechanical and thermal properties. The accuracy and resolution of the fabricated parts were high with 3DPSLR11 for stereolithography in 3D printing, which showed that 3DPSLR11 has potential application value as 3D printing material.

The market for ultraviolet curing technology has been growing at double‐digit rates in the last 10 years. The main reason for such a rapid technological growth of UV curing is its unique process characteristic, which allow UV‐coating to be applied on virtually any substrates, including plastic, metal, composite, wood, paper, leather, vinyl, glass, magnetic recording tape and even human teeth. The original driving forces behind the commercialisation of UV‐technology were energy saving and freedom from solvents. These benefits are complemented by high productivity and subsequently higher profits that can be achieved with the increased line speed, just‐in‐time benefits and immediate “pack and ship” capabilities. This paper gives a review of the development of the UV curing technology, with emphasis placed on relevant chemistry.

Finzel (American Paint and Coatings Journal, January 19 (1981) p. 19; Metal Finishing, June (1982) p. 49) has authored two review articles on silicones. He points out that silicones are mature products having first been introduced over thirty years ago. Their major use in the coatings field is for maintenance to provide protection against weathering, temperature extremes, and corrosive atmospheres. Silicones, when combined with other vehicles, impart increased resistance to moisture, chemicals, ultraviolet degradation, thermal shock, chalking, fading, and peeling. The major use, however, for silicones is for high temperature coatings as reactive intermediates and as paint additives.

This paper aims to demonstrate the synthesis of polyesterification reaction of non-edible jatropha seed oil (JO) and acrylic acid, which leads to the production of acrylated epoxidised-based resin. To understand the physico-chemical characteristics when synthesis the JO-based epoxy acrylate, the effect of temperature on the reaction, concentration of acrylic acid and role of catalyst on reaction time and acid value were studied.

First, the double bond in JO was functionalised by epoxidation using the solvent-free performic method. The subsequent process was acrylation with acrylic acid using the base catalyst triethylamine and 4-methoxyphenol as an inhibitor respectively. The physico-chemical characteristics during the synthesis of the epoxy acrylate such as acid value was monitored and analysed. The formation of the epoxy and acrylate group was confirmed by a Fourier transform infrared spectroscopy spectra analysis and nuclear magnetic resonance analysis.

The optimum reaction condition was achieved at a ratio of epoxidised JO to acrylic acid of 1:1.5 and the reaction temperature of 110°C. This was indicated by the acid value reduction from 86 to 15 mg KOH/g sample at 6 hours.

The JO-based epoxy acrylate synthesised has a potential to be used in formulations the prepolymer resin for UV curable coating applications. The JO which is from natural resources and is sustainable raw materials that possible reduce the dependency on petroleum-based coating.

The epoxidised jatropha seed oil epoxy acrylate was synthesised, as a new type of oligomer resin that contains a reactive acrylate group, which can be alternative to petroleum-based coating and can used further in the formulation of the radiation curable coating.

HIGH SOLIDS COATINGS Review Articles Without question, the major motivation for high solids coatings is government regulations. An interesting article which summarises what the coatings industry has done in order to meet air pollution regulations in the United States has been provided by Burger (Metal Finishing, July, 1982, p. 59). His list includes, in addition to high build and solventless coatings, electrodeposition, electrostatic powder coatings, Rule 66—acceptable solvent‐based coatings, and water‐borne coatings. Air pollution results not only from solvents but from the particulates released during surface preparation. Pollution due to surface preparation has been alleviated by the use of white water sandblasting, centrifugal and rotary blast cleaning blast cleaning with carbon dioxide pellets, improved ventilation air filters and safety equipment, plasma arc and laser cleaning, sonic cleaning, special chemical cleaning, and surface preparation and vacuum blasting. In addition, solvent recovery units have been utilised extensively in industrial coatings.

A variety of thermoplastic and thermosetting polymers may be employed as binders in powder coating formulations. Some typical applications of various powder coatings are shown in Table 1.

Various companies, including Dow Chemical, Dow Corning, PMC Specialities, Vanderbilt Corporation and Kusumoto Chemicals, with a long history of service to the paint, printing ink and allied industries, are represented. Products featured include antimicrobials, cellulose ethers, resins, propylene glycol ethers, silicones and a variety of speciality additives designed to meet the demand within surface coatings for improved properties.

Faster, more automated means for curing coatings as well as techniques in which the monomer polymerises to the polymer during curing readily captured the paint industry's imagination. Such concepts spell greater efficiency, greater automation and, in the long run, lower costs and greater profitability. Electron beam curing and ultra‐violet curing have emerged as the two most formidable contenders in this new area. Both methods make possible curing at near ambient temperature and both rely on high energy radiation — a highly effective form of energy for chemical reactions.

The purpose of this investigation was to study a transparent coating based on organic silicone resins prepared by the hydrolysis and condensation of methyltriethoxysilane and tetraethoxysilane.

The coating film was characterized by IR, UV, thermal gravity analysis, scanning electron microscope and an automatic contact angle meter. Some properties of the coating film, such as adhesion, impact resistance and wear-resistance also were evaluated.

These uniform, clear and smooth coating films possessed the high transparent and light transmittance, high density, high hydrophobicity, good adhesion, hardness and anti-corrosion.

The coating may be considered as a protective film for the surfaces of the metals and plastics.