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The purpose of this paper is to synthesise a novel wet-rubbing fastness improver with diphenylmethane diisocyanate (MDI), polyethylene glycol (PEG), dimethylol propionic acid (DMPA), diethylenetriamine and epichlorohydrin.

The synthetic reaction was carried out through three steps: pre-polymerising, chain-extending and chemically modifying. The influence of monomers dosage and ratio, temperature and time on reaction system and wet-rubbing fastness of reactive dye is studied. The target product was characterised by transform infrared spectroscopy analysis.

The optimum synthetic process condition of the improver is as follows: reaction temperature 100°C; pre-polymering time 2.5 hours with R value [n(NCO): n(OH)] 1.35 and DMPA 7 per cent (on percentage of total moles of MDI and PEG); chain-extending time 30 minutes with diethylenetriamine 1.5 per cent (on percentage of total moles of MDI and PEG); modifying time 2 hours with diethylenetriamine : epichlorohydrin = 1:2 (mole ratio).

The synthetic product is a three-functions-in-one (filming, salt-forming and cross-linking) wet-rubbing fastness improver which can obviously improve the wet-rubbing fastness of reactive dyes from Grade 2-3 to Grade 4.

The wet-rubbing fastness improver is novel and could find numerous applications in dyeing and finishing.

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 purpose of this study was to analyze the influence of epichlorohydrin (ECH) concentration and reaction time on the food-grade resistant starch production and its pasting properties by using native cassava starch of Misiones-Argentina origin.

Cassava starch was modified using ECH (0.30 and 0.15 per cent) during 4 or 8 h. Digestibility was evaluated by determining resistant starch as total dietary fiber. Pasting properties and the cross-linking degree were studied using a micro-viscoamylograph (Brabender).

Resistant starch content was not influenced by ECH concentration and reaction time. Cross-linking was detected at higher reaction times (8 h) and ECH concentrations (0.30 per cent), where a decrease in viscosity peaks by more than 80 per cent was observed. Both pasting temperature and breakdown were increased, whereas a decrease in retrogradation was detected.

Starches can be suitable for different food applications. This is because of the ability to modify its pasting properties and the invariability of the in vitro digestibility of cassava starch as a result of using ECH (at concentrations approved by local and regional legislation) and reaction times of 4 and 8 h.

Information related to the modification of cassava starch using ECH is scarce or not available nowadays in literature.

Egyptian cotton straw powder was acid hydrolized in presence of coal tar phenols fraction (b.r. 170–185°C) to give the phenols‐furfural resin. Homopolyepoxy resin was prepared via condensation of epichlorohydrin with phenols‐furfural resin. Similarly copolyepoxy resin was also prepared from epichlorohyhdrin, phenols‐furfural resin and prepared bisphenol A based on coal tar phenols fraction. A study of curing these epoxy resins at 170–185°C with phthalic or maleic anhydride also curing at room temperature with amine was carried out. Also the effect of the addition of kaolin as a filler was investigated to find the optimum condition which allow the cured resin to act as wood adhesive. The obtained results were comparable with those of some commercial adhesives.

The purpose of this paper is to study the effect of various stoichiometric ratios for synthesised epoxy phenolic novolac (EPN) resins on their physicochemical, thermomechanical and morphological properties.

In the present study, EPN (EPN-1, EPN-2, EPN-3, EPN-4 and EPN-5) resins were synthesised by varying five types of different stoichiometric ratios for phenol/formaldehyde along with the corresponding molar ratios for novolac/epichlorohydrin. Their different physicochemical properties of interest, thermomechanical properties as well as morphological properties were studied by means of cured samples with the variation of its stoichiometric ratios.

The average functionality and reactivity of EPN resin can be controlled by controlling epoxy equivalence as well as cross-linking density upon its curing as all of these factors are internally correlated with each other.

Epoxy resins are characterised by a three-membered ring known as the epoxy or oxirane group. The capability of the epoxy ring to react with a variety of substrates imparts versatility to the resin. However, these resins have a major drawback of low toughness, and they are also very brittle, which limits their application in products that require high impact and fracture strength.

Epoxy resins have been widely used as high-performance adhesives and matrix resins for composites because of their outstanding mechanical and thermal properties. Because of their highly cross-linked structure, the epoxy resin disables segmental movement, making them hard, and it is also notch sensitive, having very low fracture energy.

Epoxy resin is widely used in industry as protective coatings and for structural applications, such as laminates and composites, tooling, moulding, casting, bonding and adhesives.

Systematic study has been done for the first time, as no exact quantitative stoichiometric data for the synthesis of EPN resin were available on the changes of its different properties. Thus, an optimised stoichiometric composition for the synthesis of the EPN resin was found.

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions. The structures of the intermediate and final products were characterized by FT-IR (Fourier transform infrared spectroscopy analysis), ¹H-NMR (proton nuclear magnetic resonance spectroscopy) methods. The thermal performance of surfactants was analyzed using thermogravimetric analysis (TGA). The thermogravimetric results showed that the sulfate-based Gemini surfactants had good heat resistance (the thermal decomposition temperature of which was in the range of 140∼170?). The Krafft point, surface tension, foaming, Hydrophile–Lipophile Balance Number (HLB), emulsifying, wetting, and lime-soap dispersing performance were measured by visual observation, hanging drop method, aqueous surfactant solution method and Borghetti–Bergman method, respectively. The results have shown that all the sulfate-based Gemini surfactants had good water solubility and lime-soap dispersing ability. When spacer group was -(CH2)2-, with the increase of the carbon chain length from C12 to C14, the micellar concentration critical micelle concentration and surface tension (CMC) gradually increased from 8.25 × 10^–4 mol/L to 8.75 × 10^–4 mol/L and 27.5 mN/m to 30.9 mN/m, respectively. Also, the sulfate-based Gemini surfactants with the different length of the spacer group had a different effect on their performance on foaming properties and foam properties, HLB and emulsifying ability and wetting ability.

In view of the important role of the spacer group and the general use of anionic surfactants in oil fields, this article considers the preparation of a series of sulfate-based Gemini surfactants by changing the spacer group and the chain length of the hydrophobic group and evaluating their surface activity, and finally its Kraffi, on the foam properties, HLB value, emulsifying performance, lime soap dispersing ability etc.

Sulfate-based Gemini surfactants have broad application prospects in the fields of oil and gas exploitation, environmental protection, chemistry and daily chemical industry and so on.

The purpose of this study is to improve the coating properties of shellac–epoxidised novolac blends by treatment with melamine formaldehyde resin (MF) at ambient temperature for its use as a coating material.

Epoxidised-novolac resin was synthesised by epoxidation of novolac resin with epichlorohydrin. Novolac resin was synthesised by reaction of phenol with formaldehyde in acidic medium. Shellac was blended with the epoxidised-novolac resin in solution in varying ratios and treated the blends with MF resin in fixed ratio. Coating properties of the treated compositions were studied using a standard procedure. The compositions were characterised with Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and scanning electron microscopic (SEM) spectroscopy.

Treatment of shellac–epoxidised-novolac blends with MF resin improved water and alkali resistance of the blends, besides enhancing gloss. Gloss in all the blends was uniformly increased on treatment with MF resin. Water resistance of the blends tremendously improved after treatment with MF resin. Contact angle of the blends against water increased while decreased against ethylene glycol and dioxane. The compositions were more resistant to polar solvent than non-polar ones, suggesting that the compositions shifted to hydrophobic (lipophilic) nature on treatment with the MF resin.

A specified concentration of MF resin was used in the study. Different concentrations of the MF resin can also be tried for treatment of shellac–epoxidised-novolac blends to see the effect of the resin on the blends.

Treatment of shellac–epoxidised-novolac blend with MF resin improved the coating properties of the blends. The formulation SeNB-64 is the best with high gloss, good impact, scratch hardness and water resistance, and hence can be used as coating material for metal surfaces.

Blending of shellac with epoxidised-novolac resin and treatment of the blends with the MF resin was done for the first time. The formulation SeNB-64 can be used as coating material for metal surfaces.

The paper's purpose is to optimise lab‐size synthesis process of a fluorene‐containing epoxy resin, characterise structure of the resulting epoxy resin and evaluate mechanical properties of the cured fluorene‐containing polymers.

The synthesis of the fluorene‐containing epoxy resin was accomplished by the polycondensation of 9,9‐bis(4‐hydroxyphenyl)‐fluorene and epichlorohydrin in the presence of quaternary ammonium salt and composite solvent under vacuum. The chemical structure of epoxy resin thus obtained was characterised with FTIR, NMR and MS. The shear strengthes of cured fluorene‐containing epoxy resin were determined and compared with that of cured E‐44 bisphenol A epoxy resin and F‐44 novolac epoxy.

The epoxide equivalent weight (EEW) of the fluorene‐containing epoxy resin reached 240‐246 g/mol under optimal epoxidising condition. The resulting epoxy resin exhibited approximate high temperature performance relative to F‐44 novolac epoxy, much better heat resistance than that of E‐44 epoxy resin and lower moisture uptake than that of the two above‐described resins.

The shear strength of cured fluorene‐containing epoxy resin was relatively low at ambient temperature, whereas was much higher than that of bisphenol A epoxy resin at higher temperature, making it a potential candidate for many applications such as high temperature adhesives, coatings and matrix resins for advanced composite.

The method for preparation was modified and improved, structure characterisation was comprehensive. The material prepared could find numerous applications as heat‐resistant adhesives and matrix resins.

To prepare modified epoxy resins from resorcinol, cresol and phenol for improved adhesion and chemical resistance. To evaluate the properties of such modified epoxy resins.

Epoxy novolac resins (ENRs) were synthesised by condensing epichlorohydrin with novolacs based on different types of substituted phenols for improving adhesion and chemical resistance. Various compositions were made by incorporating different proportions of polyamide resin. The chemical and adhesive strengths of the conventional epoxy and the modified epoxy resins were characterised.

The modified ENR using substituted phenols showed significant enhancement of chemical and adhesive strengths over the conventional DGEBA resin. The modified ENR had an increased number of glycidyl groups (thus increased functionality) of resin, which was responsible for improved chemical and adhesive strengths over the conventional DGEBA resin.

The EPN resins used in the present context was synthesised from phenol, resorcinol and cresol and cured by polyamide resin of different amine values. Besides, it could be synthesised from phenolphthalein p‐aminophenol and p‐ter‐butylcatachol, etc.

The method developed provided a simple and practical solution to improving the adhesive and chemical resistance of cured epoxy phenol novolac resins.

The method for enhanced adhesive and chemical resistance of cured epoxy was novel and could find numerous applications in surface coating and adhesive.