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The purpose of this paper was to show that the generalised viscosity model can correctly characterise suspension data over both a wide range of concentration as well as a wide range of temperature. A second objective of this study was to show theoretically and experimentally how the interaction coefficient from the generalised viscosity model also appears to have some thermodynamic properties.

In this study, many well‐known suspension equations were shown mathematically to be subsets of the generalised viscosity equation. The generalised viscosity equation was also found to be able to be reduced mathematically to two well‐known dilute solution equations (Huggins and Kramer's equations) as well. The relationship between Huggins and Kramer's constants and the interaction coefficient from the generalised viscosity equation yielded the potential to evaluate the solubility characteristics of the interaction coefficient. The value of the interaction coefficient was then found to be able to be evaluated as a function of temperature to enhance an understanding of the thermodynamic characteristics of the interaction coefficient using the data of Bueche.

In this study, a polymer plasticiser system involving polymethyl methacrylate in the plasticiser diethyl phthalate yielded an interaction coefficient, σ, primarily in the expected plasticiser range from 0< σ<1. It was also found that the generalised viscosity equation fit Bueche's polymer plasticiser data remarkably well over the whole concentration range for temperatures ranging from 30°C to 140°C. This study also appeared to show that the interaction coefficient from the generalised viscosity model can apparently characterise thermal transitions as well as thermodynamic solubility for a polymer solute (i.e. polymethyl methacrylate) when viscosity is evaluated over a wide temperature range. This result was particularly significant since Bueche's data covered 25 decades of viscosity on a log scale.

This is the first paper to successfully explore the thermodynamic characteristics of the interaction coefficient of the generalised viscosity equation. This opens up new avenues for evaluating the solubility and thermodynamic characteristics of various additives in solutions and polymeric formulations.

Presents a hyperbranched polymer, a hydroxyl functional aliphatic polyester which consists of a polyalcohol core from which branches extend, forming a core‐shell structure with a large number of hydroxyl groups at its peripheral surface. It is polydisperse and consists, apart from the main core/shell fraction, of a minor fraction with tree‐like branches. Hyperbranched polyesters of this type have been found to contribute to improved physical, as well as chemical and mechanical, properties. Due to the unique molecular architecture, it is possible to design the hyper‐branched polyester in numerous ways to acquire the desired properties in different applications. Focuses on and illuminates how molecular design might affect properties in not only one, but many applications. Illustrates this by way of examples in the field of alkyds, where presented hyperbranched polymer contributes to low viscosities combined with excellent drying; in amine cured epoxies, where a hyperbranched epoxy demonstrates dramatically increased toughening; and in polyurethanes and radcure, where rapid curing can be obtained by proper molecular design.

The effects of ultrasonication on the epoxy resin and its emulsion were investigated to find out the changes in the M_η and molecular structure of epoxy, as well as its room temperature storage stability, centrifugal stability, particle size and its distribution and particle morphology more importantly with the influence of different ultrasonic irradiation time, power and temperature.

The emulsion was prepared using an emulsifier with epoxy resin and by using phase inversion after subjecting to ultrasound irradiation with a power of 200 W at 50°C for 60 min. The changes in the epoxy resin and its emulsion induced by ultrasound were characterized by Ubbelohde viscometer, FT-IR, ¹³C-NMR, high-speed desktop centrifuge, laser particle size analyzer and transmission electron microscope.

The molecular weight of the epoxy resin was initially decreased and then stabilized by the increasing of ultrasonic irradiation time. The mole rate of the epoxy groups in epoxy molecular were decreased by about 14 per cent, resulting from ultrasonic irradiation. The particle size of the emulsion was decreased, while the particle size distribution became uniform in a certain time. The narrow distribution, stable and uniform of waterborne epoxy resin emulsion with more than 60 days room temperature storage period, 80 per cent of the supernatant volume, about 220 nm average particle size was gained with a power of 200 W at 50°C for 60 min.

To overcome the problems commonly encountered with an epoxy emulsion, for example, short storage period and wider particle size, which limit its practical application, the effects of ultrasonic irradiation on the epoxy resin and its emulsion, were investigated. As the stability of emulsion was improved with the introduction of ultrasonic irradiation, the application of epoxy emulsion was improved.

The room temperature storage stability and centrifugal stability of the emulsion were decreased by the mechanical method, and thus, the benefit of an in-depth understanding of the influence of ultrasonic treatment on epoxy resin and its emulsion could further promote the development of water-based coatings.

The purpose of this paper is to find a new curing agent for diglycidyl ether of bisphenol A (DGEBA) resin and to check effectiveness of this new curing agent to obtain toughness and chemical resistance of cured epoxy.

For this purpose, an investigation was carried out to synthesise, characterise and to study curing reaction of amine functional aniline acetaldehyde condensate (AFAAC) with DGEBA resin. AFAAC was first synthesised from the reaction of aniline and acetaldehyde in acid medium and characterised by FT‐IR, ¹H‐NMR spectroscopic analyses, elemental analysis, concentration of primary and secondary amine analysis. Then equimolecular mixture of AFAAC 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, mechanical properties, dynamic mechanical analysis and thermogravimetric analysis (TGA) of cured epoxy were also reported.

The DSC analysis showed the complete exotherms of effective curing reaction indicating the efficiency of AFAAC as curing agent for DGEBA resin. The kinetic studies revealed that the curing reaction was first order. Mechanical properties reflect the better fracture properties of cured matrix and TGA showed that the cured matrixes were stable up to around 238°C.

The curing agent AFAAC has been synthesised by using aniline and acetaldehyde. 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, adhesives for most substrates.

Hyperbranched poly(ester-amide)s (HPEAs) have been synthesized from diethanolamine and maleic anhydride with ethylene glycol as a core monomer by using a two-step method, which are marked as Hupea polymers, and dehydration was carried out in xylene under reflux.

In comparison with Hupea polymers was synthesized by one-pot method, Hupea polymers synthesized by two-step method has different structure and rheological properties. The intermediate monomer and the resulting polymer are characterized by FTIR and NMR spectroscopies.

All of Mw, Mn and Mw/Mn of the hyperbranch polymers decrease with the core/monomer molar ratio increasing. The intrinsic viscosity ([η]) of the polymers decreases with Mw increasing in the investigated range of Mw and scales as [η]∼Mw-0.82, which implies that the molecular weight grew faster with core/monomer molar ratio decreasing than the volume in the investigated range of core/monomer molar ratio.

The hydrodynamic radius was calculated by using Einstein’s equation and scales as Rh ∼ Mw0.061, and the lower exponent reveals the slow growth in the volume of Hupea molecule. In addition, the viscosity of Hupea polymer in concentrated aqueous solution is independent of shear rate and slightly dependent on molecular weight.

Hyperbranched poly(ester-amide)s (HPEAs) were synthesized by using a two-step method, which had different structure and rheological properties.

Hupea polymers show different features from Hupea polymers in structure and rheological properties, which revealed that the synthesis process of HPEA has effect on its performance.

Epoxy resins have probably provided more interesting chemistry than any other polymer the paint industry uses. In this category of interesting chemistry is Russian work [World Surface Coatings Abstracts (1978) Abstract No. 1558] which describes the preparation of structurally coloured epoxy resins — i.e. of epoxy resins which are inherently coloured. The work involves condensing bisphenol A and epichlorohydrin in the presence of small amounts (0.1 to 0.5 weight per cent) of a coloured co‐monomer dye. The dye, for example, can be the glycidyl ether of alpha aminoanthroquinone. Coloured products resulted which presumably would provide coatings with intrinsic colour. Of course, this colour could be modified by extrinsic dyes and pigments. The concept of producing coloured polymers is not a new one. One approach to making black polyethylene for black film is to carry out the polymerisation of the ethylene in a fluid bed of carbon particles. The carbon particles presumably serve as a nucleus around which the polymer forms and at the same time serves to impart a black colour to the polymer particle. This technology has never been commercialised but it is certainly of interest to the paint chemist for it presents a new concept in carrying out a major objective of the paint industry — namely, to impart colour to solutions of polymers.

The effects of catalysts used to promote the reaction of epoxy‐anhydride mixtures was studied by Nuss (77) using a GPC technique. It was demonstrated that when the polymerisation reaction occuring in an identical system was monitored, in the presence of different catalysts, the relationship between the apparent molecular size distribution and the lapsed time of the curing reaction was a function of the catalyst employed.

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.

This study aims to systematically compare the effect of increasing fiber–matrix interface adhesion and matrix toughness in layered composite materials.

Silane ((3-glycidyloxypropyl) trimethoxysilane) was applied to strengthen the fiber–matrix interface connection in e-glass/epoxy laminated composite material. Using a cationic surfactant, 0.1% multi-walled carbon nanotubes (CNTs) were added to the matrix in two different ways, by with and without chemical functionalization using the vacuum infusion method.

In the results obtained from the three-point bending test specimens, it was determined that the synergistic effect of silane application and non-functionalized CNT in the matrix was higher in terms of flexural modulus and strength values.

The functionalization of multi-walled CNT did not give the expected results because of reasons such as viscosity increase and agglomeration in the matrix.

In this study, a simple model for normalization and prediction purposes was developed, which allows the determination of the flexural modulus and un-notched flexural strength values from one test result of the notched specimen. A systematic comparison was performed by varying each parameter in the composite material.

This paper aims to present a new fabrication method for fuel cell current collectors. Demonstration of its usefulness and discussion of its impact on current collector design and performance are also given.

The selective laser sintering (SLS) technique is used to create green parts followed by a high temperature curing process and pressureless infiltration treatment to meet basic part design requirements.

A material system and process satisfying both manufacturing constraints and product property requirements can be used for fabrication of current collectors via SLS. Relative particle size and composition of the constituents play an important role in successful manufacture of the plates. Strategies to improve electrical conductivity are also discussed.

A new manufacturing method has been developed for the construction of fuel cell current collectors that could generate opportunities for performance enhancement and fuel cell application by eliminating the constraints imposed by traditional fabrication processes.