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This paper reports the characterization of a photosensitive benzocyclobutene (BCB), a low dielectric constant spin‐on polymer for use as interlayer dielectric in the microelectronics industry. Research work is divided into three main sections. First, BCB thin film characterization was done to investigate the effects of curing conditions on BCB film thickness, dielectric properties, optical properties and extent of cure. Thermal stability of BCB was then evaluated using thermogravimetric analysis (TGA) to detect weight loss during thermal curing and degradation. Finally, curing kinetics study was conducted using both differential scanning calorimetry (DSC) dynamic (American Society for Testing and Materials method) and isothermal approaches. The first study shows that determination of vitrification point during thermal curing of BCB is crucial to predict film properties. By curing to just before vitrification, lowest refractive index, hence dielectric constant, could be obtained.

The authors are experienced researchers in the selection, evaluation and simulation of polymeric matrix resins for advanced composites. This article reviews the current state‐of‐the‐art in cure monitoring techniques and the application of modern computational methods to determine the kinetics of cure in commonly used aerospace systems. Extensive reference is made to primary sources and conclusions drawn about the possible future developments that may evolve in this area of interest.

The curing reaction of a promising “no flow” flip chip underfill encapsulant is investigated by using a differential scanning calorimeter. It is found that the tested underfill can reach complete cure within 20 minutes at various cure temperatures. It is also shown that this “no flow” underfill could fully cure within one minute at 160°C after being heated at 220°C for one minute, demonstrating that this “no flow” underfill can be completely cured during the solder reflow cycle. The reaction order and the rate constant are determined to describe the curing progress. It is shown that the autocatalytic effect dominates the reaction kinetics.

The purpose of this paper was to check effectiveness of amine functional chloroaniline acetaldehyde condensate (AFCAC) as a new curing agent for diglycidyl ether of bisphenol A (DGEBA) resin. For this purpose, first AFCAC was synthesised, characterised and then curing reaction was carried out.

Equimolecular mixture of AFCAC and DGEBA was subjected to curing reaction, and the reaction was followed by differential scanning calorimetry (DSC) analysis. The kinetic studies of this curing reaction were also carried out from those DSC exotherms. The mechanical properties, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) of cured epoxy were also reported.

DSC results reflected the effective first order curing reaction of AFCAC with epoxy resin. Mechanical properties reflected appreciable rigidity of AFCAC cured epoxy matrix and TGA showed that the cured epoxy networks were thermally stable up to around 297°C.

The curing agent AFCAC was synthesised by using chloroaniline and acetaldehyde in acid medium. There are some limitations for this procedure. The synthetic procedure is pH dependent. So reaction cannot be done at any pH value. The reaction must also be carried out at room temperature without any heating. To obtain low molecular weight curing agent, chloroaniline and acetaldehyde cannot be taken in equimolecular ratio because the equimolecular mixture of them produces high molecular weight condensate. This was shown in our previous publication. Some implications are also there. By changing amine and aldehyde other curing agents could be synthesised and the curing efficiency of those for epoxy resin could also be studied.

Experimental results revealed the greater suitability of AFCAC as curing agent for DGEBA resin and novelty of AFCAC cured matrix in the field of protective coating, casting, adhesives, etc.

During recent years, the PCB industry has become more aware of the use of analytical test techniques to aid in materials testing. Repeatable quality of base materials, together with the monitoring of the production process and the finished product, has caused supplier and fabricator to consider existing methods and to see whether modern instrument techniques can improve such tests. During meetings such as Internepcon and Productronica, the author has presented developments by DuPont which have used Thermal Analysis techniques to evaluate the materials and processes involved in the manufacture of a multilayer printed circuit board. The purpose of this paper will be to give an up to date review of the work. It will discuss the successes to date and will show where modifications to experimental methods have been made to give more practical data. Specific test methods currently used in the industry will be discussed and recommendations will be made showing Thermal Analysis techniques may offer a more objective test as well as giving the user time savings and a reduction in manpower through increased instrument productivity and versatility.

The purpose of this paper is to study thermal stability, curing kinetics and physico‐chemical properties of polyurethanes systems for application in in‐mould decoration (IMD) ink.

The thermal stability of three Polyurethane (Pu) systems A, B, C were evaluated by thermogravimetric analysis (TGA). The kinetic parameters of the curing reaction of Pu system C were calculated using non‐isothermal curing kinetics analysis, including the activation energy Ea, the reaction rate constant K(T), the reaction order n, the initial curing temperature (Ti), the peak temperature (Tp), and the finishing temperature (Tf). Additionally, physico‐chemical properties were also evaluated such as flexibility, impact resistance, pencil hardness, adhesive attraction and solvent resistance.

TGA showed that thermal decomposition temperature T5 (5 wt.% weight loss), T10 (10 wt.% weight loss) and Tend (decomposition termination temperature) of Pu system C was 344°C, 363°C, and 489°C, respectively. T5, T10, Tend increased by 77°C, 61°C, 4°C, respectively, and the char yield at 600°C increased by 25.1 wt.% comparing with Pu system B. Curing kinetics analysis showed that Ea of Pu system C was 62.29 KJ/mol, 65.98 KJ/mol and 65.95 KJ/mol by Kissinger, Flynn‐Wall‐Ozawa and Ozawa method, respectively. The order of the curing reaction (n=0.90) demonstrated that it was a complex reaction. Moreover, Pu system C exhibited good physico‐chemical properties. The results showed that Pu system C was suitable to apply into IMD ink.

The TGA analysis, curing kinetics analysis and evaluation of physico‐chemical properties provided a simple and practical solution to study suitable resins for IMD ink application.

IMD ink for heat transfer printing technology is highly efficient, relatively low cost, clean and environmentally safe. It has been widely applied into medical and pharmaceutical products, electronic devices, telecommunication equipment, computer parts, appliance panels, automotive parts, etc.

In this paper, the thermal stability and curing kinetics of Pu for IMD ink are reported for the first time. The paper gives very interesting and important information about thermal stability, curing kinetics and properties of Pu coating system for IMD ink application.

In order to study its cure response and to understand its kinetic behaviour, this paper seeks to examine how a multifunctional epoxy resin, N,4‐bis(4‐(bis(2‐oxiranylmethyl)amino)‐2‐chlorobenzyl)‐3‐chloro‐N‐(2‐oxiranylmethyl)benzenamine (BCCOMB), synthesised from amine functional chloroaniline formaldehyde condensate (AFCFC) and epichlorohydrine, is cured with AFCFC as curing agent.

For effective curing, AFCFC (12.5 phr, part per 100 resin) was added to BCCOMB resin and mixed thoroughly for 15 minutes. The clear viscous solution was then subjected to DSC analyses for kinetics study of the curing reaction.

The AFCFC was successfully utilised as curing agents for BCCOMB as the DSC curves show complete curing exotherm. The presence of oxirane group in the BCCOMB was able to react with active hydrogen atoms of amine. This led to conversion of liquid monomers of thermoset resin into three‐dimensional network.

In the present discussion, the curing study of BCCOMB had been done using AFCFC as a curing agent. However, other curing agents, synthesised from other amine and aldehyde, could also be used to see whether they would be effective for curing study of BCCOMB.

The method for curing study of multifunctional epoxy resin (BCCOMB) was novel and the cured epoxy network could find numerous applications as surface coating and adhesive on to an intricate structure.

To prepare and characterise vinyl ester (Bisphenol‐A‐glycidyldimethacrylate (BisGMA)) prepolymer via a new synthetic route involving the esterification of methacrylic acid and epoxy resin.

BisGMA prepolymer was synthesised from methacrylic acid and diglycidyl ether of bisphenol‐A‐type epoxy resin. The compound synthesised was then purified and characterised.

BisGMA prepolymer was synthesised from methacrylic acid and diglycidyl ether of bisphenol‐A‐type epoxy resin using triphenylphosphine as a catalyst and hydroxy toluene as a stabiliser. The synthesised compound was then purified by normal phase liquid chromatography and was analysed by proton NMR and reverse phase HPLC. The cure kinetics of the purified resin was investigated by differential scanning calorimetry (DSC) using NETZSCH thermo kinetics software.

The preparation, purification and kinetics study of the prepolymer described in the present investigation may be useful for preparation, purification and kinetics study of the other vinyl esters by a new synthetic route. Also, the polymer supports based on BisGMA have acceptable mechanical properties, chemical stability and are suitable for dental restoratives, fissure sealants, coatings, adhesives, moulding compounds, structural laminates, electrical applications and military/aerospace applications.

The method for the preparation, purification and kinetics study of the prepolymer is simple and provides a simple and practical solution for some other vinyl esters.

This is a novel method for synthesis and purification of BisGMA and may be useful for the synthesis and purification of other vinyl esters.

This paper seeks to prepare and characterise vinyl ester (bisphenol‐A‐glycidyldimethacrylate (BisGMA)) prepolymer via a new synthetic route by the esterification of methacrylic acid and epoxy resin

BisGMA prepolymer was synthesised from methacrylic acid and diglycidyl ether of bisphenol‐A (BPA) type epoxy resin. The synthesised compound was then purified and characterised.

BisGMA prepolymer was synthesised from methacrylic acid and diglycidyl ether of BPA‐type epoxy resin using triphenylphosphine as a catalyst and hydroxytoluene as a stabiliser. The synthesised compound was then purified by normal phase liquid chromatography and was analysed by proton NMR and reverse phase HPLC. The cure kinetics of the purified resin were investigated by differential scanning calorimetry using NETZSCH thermokinetics software.

The preparation, purification and kinetics study of the prepolymer described in the present investigation may be useful for preparation, purification and kinetics study of the other vinyl esters by a new synthetic route. Also, the polymers supports based on bisphenol‐A‐glycidyldimethacrylate have acceptable mechanical properties, chemical stability and are suitable for dental restoratives, fissure sealants, coatings, adhesives, moulding compounds, structural laminates, electrical applications and military/aerospace applications.

The method for the preparation, purification and kinetics study of the prepolymer is simple and the above method provides a simple and practical solution for some other vinyl esters.

This is a novel method for synthesis and purification of BisGMA and may be useful for the synthesis and purification of other vinyl esters.

The purpose of this paper is to investigate the curing efficiency of amine functional aniline furfuraldehyde condensate (AFAFFC) for diglycidyl ether of bisphenol A (DGEBA) resin to achieve toughness, chemical resistance, etc.

To study curing reaction, the curing agent AFAFFC is synthesised first from the reaction of aniline and furfuraldehyde in acid medium and characterised by Fourier transform infrared spectroscopic analysis, elemental analysis, concentration of primary and secondary amine analysis. Then, equimolecular mixture of AFAFFC and DGEBA is subjected to curing reaction and the reaction is followed by differential scanning calorimetry (DSC) analysis. The kinetic studies of this curing reaction, mechanical properties, dynamic mechanical analysis and thermogravimetric analysis (TGA) of cured epoxy are also reported.

The DSC analysis shows the complete exotherms of effective curing reaction indicating the efficiency of AFAFFC as curing agent for DGEBA resin. The kinetic studies reveal that the curing reaction is first order. Mechanical properties reflect the brittleness of cured matrix and TGA shows that the cured matrixes are stable up to around 240°C.

The curing agent AFAFFC has been synthesised by using aniline and furfuraldehyde. By changing amine and aldehyde, other curing agents could be synthesised and the curing efficiency of these for epoxy resin could also be studied.

The method for curing study of epoxy resin (DGEBA) is novel and relevant as the cured products have high performance applications in protective coatings and adhesives for most substrates.