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Based on the superior properties of the COPNA resin laminate exhibiting Tg at 255∞C, small CTE at 5‐7 ppm (xy‐axis) and at 29 ppm (z‐axis), reliability of both two‐layered and six‐layered printed wiring boards using COPNA resin as a matrix were evaluated. In the case of the two‐layered system, it exhibited higher reliability than the FR‐4 graded epoxy‐resin laminate in the entire tests, and exhibited higher reliability than the BT resin laminate in the THB test, heat‐shock test, and heat‐cycle test. In the case of the six‐layered system, it also exhibited higher reliability than the BT system in both heat‐shock test and PC test.

The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. Many studies, including the authors’ previous study, have proved that covalent-incorporated phosphorous-containing (P-containing) monomer onto the PA resin can exhibit better flame resistance than that by an additive approach. However, other properties such as thermal stability, coating properties are still deteriorated. To further improve the flame-retardancy and other comprehensive properties of the P-containing PA resin, in this study, melamine formaldehyde(MF) resin was used not only as a curing agent to enhance the coating properties of the PA resin, but also as a nitrogen-containing (N-containing) resin to form a P-N synergistic effect and therefore further improve its flame retardancy.

Epoxy resin phosphorous acid-modified (EPPA-modified) PA (EPPA-PA) resin was first prepared and then using MF resin as curing agent. The flame retardancy of the cured resin was tested by the limiting oxygen index (LOI) and UL 94 methods. The thermal stability of the cured resin was studied by TGA. The coating technology such as adhesion property, pencil hardness and anti-solvent properties were characterized according to methods of International Standards ISO2409-1992, ISO 15184-1998 and ISO-15184-2012, respectively. The micro-char morphology of the char residue was observed by SEM.

The results showed that by using MF resin as curing agent has provided the PA resin with excellent coating properties and thermal stability, but also gave a P-N synergistic effect which has greatly enhanced the flame retardancy of the cured resin. The cured resin system containing only 1.7 Wt.% P content and 5.3 Wt.% N content can reach a LOI of 26.9 per cent and pass the V-0 rating in the UL-94 test.

This resin system releases formaldehyde due to the MF resin.

It is expected that the large-scale production of this EPPA-PA resin cured by MF resin system will enable practical industrial applications.

This method for the synthesis of a P- and N-containing PA resin system is newfangled.

Introduction Most corrosion protection systems used for maintenance, as well as binders for the building and civil engineering industries, are cold‐curing formulations. Elevated temperature cure is usually excluded by the size and shape of the substrate to be coated. Consequently, the selection of binders that are suitable for these surface protection systems is limited to those that combine the following properties:

Corrosion is an important problem to be taken care in terms of economic and ecological aspects. The aim of this paper is to identify the methods of protection and selection of materials for corrosion protection.

A novel attempt has been made to formulate a hybrid composite paint system using silicone (S2) and polyester (P3) resins. These resins have been blended in different weight ratios to develop binder for protection coatings. Cross‐hatch test, impact resistance test, thermal characterization, impedance measurement and potential‐time measurement were conducted on binder coated steel panels. Heat resistance test was carried out using ASTM D2485 standards.

The results showed that physical and mechanical properties of the coatings have been improved by the addition of silicone into the polyester matrix. The binder system developed using 50 wt per cent polyester and 50 wt per cent silicone showed good physical, mechanical properties and high thermal resistance. The maximum coating resistance of the coatings after 30 days exposure was found to be 9.7×10⁶ Ω and the coating can withstand high temperature up to 473 K.

The development of different types of coatings will be useful to achieve higher protection performance. The combinations of different resins and pigments have to be analysed and selected suitable compositions.

The objective of this study is to develop coating system with different resins to achieve better performance and reduce the cost of paint materials. It may be useful for the industries to move forward with new formulation using multicomponent coating materials. A critical combination of the above resins offers better protection for steel structures from high temperature corrosive environments.

The formulation of coating material using two different resins and a single curing agent is a novel approach in this research. This type of research will open new ideas of formulating different coatings using various types of resins. In high temperature corrosion environment, the coatings which is commonly used is silicone based and the price of the raw material is very high therefore to reduce the cost of the raw material, the silicone resin is being blended in different ratios with organic resin to obtain an optimum ratio which can be applied to overcome high temperature corrosion on steel panels.

In the past, solvents containing impregnation systems were in vogue, e.g. phenoloic‐alkyd, isophthalic polyester, silicone, etc. for electrical machines. The disadvantages of solvent borne impregnants are a higher dissipation factor (at elevated temperatures) and water absorption, etc., due to the presence of air voids formed during the curing process. The phenomenon has been controlled with the present day use of solvent/ess systems, e.g. polyester, polyesterimide, epoxy and silicone resins. Solvent/ess polyester resins are now indigenously available along with their additives such as: inhibitor, catalyst and reactive diluent, etc. Modern methods of impregnation for electrical machines in BHEL include: (a) Dip impregnation by rotational method (b) V P I process The methods include storing the catalysed resin in cool storage, warming for impregnation, and final impregnation under vacuum and pressure, and curing in an oven. A monitoring system has also been standardised for the impregnation resin to keep its viscosity and gelling time within the specified tolerances by the addition of an appropriate amount of inhibitor and reactive diluent. Proper monitoring keeps the tank life of the system indefinitely long and its properties within limits.

There are many considerations that have to be taken into account when balancing the properties epoxy‐based laminate and prepreg materials must have in order to meet the array of electrical, thermal and mechanical demands of today's multilayer printed circuit boards. Aims to discuss two different curing systems that are commonly employed in current laminate and prepreg materials.

An examination of the two different curing systems – phenol novolac (PN) and dicyandiamide (DICY) based – that are commonly employed in current laminate and prepreg materials.

DICY curing systems have properties such as good flexibility, good adhesion and good processability but have poor thermal resistance, higher water absorption and poor anti‐CAF capability. Because PN resin systems utilize an aromatic ring structure, traditional PN cured epoxy resin results in having excellent thermal resistance, low water absorption and anti‐CAF capability.

Provides a comparison of interest to all those involved with laminate and prepreg materials in the circuit board industry.

There are many advantages to be gained from the use of water, rather than toluene, or other typical solvents used in the application of epoxide resin paint systems, as the comparison in table 1 shows:

The purpose of this paper is to investigate the effects of various catalyst contents, resin solid contents, catalyst species and wood extract on urea‐formaldehyde (UF) curing by differential scanning calorimetry (DSC) technique. The finding obtained would benefit the manufacturers of UF‐bonded composite panels.

The UF curing rate under each condition in terms of DSC peak temperature was measured by high‐pressure DSC at a heating rate of 15°C/min; the correlations of peak temperature with catalyst content, resin solid content, catalyst species and wood extract, respectively, were regressed via a model equation, which described the curing characteristics of the UF bonding system.

A model equation, T_p=A · EXP(−B · CC per cent)+D, was proposed to characterise the DSC peak temperatures or the rate of UF curing with regressing coefficients greater than 0.97 (commonly greater than 0.99). The constants A and B in the model equation were found to correspond to kinetic characteristics of UF resin curing reaction. The constant D in the model equation is believed to be associated with the utmost peak temperature, which implies that the DSC peak temperature will finally reach a maximum with catalyst content increasing. It was also found that the wood extracts having higher pH value and base buffer capacity had stronger catalyses on UF curing.

The catalysts commonly used in medium density fibreboard plants or particleboard plants are those having the utmost peak temperature of about 90‐95°C; the catalyses of wood extracts were much weaker than that of catalyst NH₄Cl.

The model equation could be used to predict the peak temperature or the curing rate of UF resin, and to quantify the effects of wood extracts on UF curing.

The study developed a model equation that can well characterise the UF curing, and quantified the effects of wood extracts on UF curing.

ABM Chemicals Ltd is exhibiting its range of photosensitisers for uv curing including the Glocure benzoin ethers. These highly cost effective materials ensure maximum utilisation of uv energy for the polymerisation process.

In the manufacturing process for making printed circuit boards (PCB) it is necessary to drill holes in the base copper clad laminate. This is a crucial step in the case of multi‐layer boards where the holes must be plated with copper to complete the electrical connection between the layers. Drilling is an expensive process as it requires the use of extremely sophisticated equipment. Most often this resides with a handful of companies; namely board shops and drill bit manufacturers. In recent years, with the evolution of high performance resins such as high glass transition (T_g) and decomposition temperature (T_d) as well as low dielectric constant (D_k) and the continued embracement of the use of phenolic cured resins compared to dicyandiamide (DICY), issues around drillability have increased. As a part of our efforts we compared the mechanical and thermo‐mechanical properties of three resins. Actual drilling studies were performed on three‐high, copper clad stacks made from these three resins at Megatool in California, in order to confirm our fundamental property correlations. Resin toughness was found to play a crucial role in the final PCB drillability.