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The purpose of this paper is to develop eco‐friendly coatings based on low‐cost epoxide resins prepared by using a natural phenolic material such as cardanol (non‐toxic), in place of ordinary phenol (toxic), which can be self‐curable at an optimum temperature.

Cardanol‐formaldehyde novolac resins (CNs) were prepared by reacting cardanol with formaldehyde in different molar ratios varying from 1:0.6 to 1:0.9. Prepared CNs were epoxidised by reacting with epichlorohydrin to produce epoxide resins, which would be called as epoxidised CNs (ECNs). Further, ECNs were modified by reacting with diethanolamine (DEtOA), a secondary amine to introduce tertiary amino group(s) into the molecules, required for self‐curability of ECNs. These modified ECNs are referred to as MECNs. The molar ratio of ECNs to DEtOA was taken in accordance with epoxy functionality of epoxide resins (ECNs) which ranged from 0.5 to 2.9. Nine numbers of MECNs (MECN₁ to MECN₉) were prepared by using four epoxide resins. These resins viz. CNs, ECNs and MECNs were characterized by ¹H NMR and FTIR spectroscopic methods for their structure elucidatation, and by gel permeation chromatography for determining their molecular weights.

The most suitable molar ratio of ECN:DEtOA for the preparation of MECNs was found to be 1:1. The CN prepared by using cardanol and formaldehyde in the molar ratio of 1:0.7 was used for the preparation of ECN₂ and MECN₂. Applied films of epoxide resins, designated as MECN₂, had reasonably good physical and chemical resistance properties. With a wide cure window, the films of MECN₂ were found to be self‐curable at an optimum cure schedule of 160°C/30 min. Owing to self‐curability of the developed epoxide resins, the coatings based on them did not require any additional/external crosslinker to be incorporated in the coating composition.

The prepared epoxide resins (MECNs) had good physical and chemical resistance properties, but demonstrated low stability and low resistance to xylene, in particular.

The paper shows how the epoxide resins were prepared by using a low‐cost phenolic material (cardanol) which is obtained from natural renewable resources, instead of petroleum, and is non‐toxic. These developed coatings can be applied as primer coat and top coat on metallic substrates. True self‐curability of the coating films has been achieved via anionic polymerization.

The purpose of this paper is to modify the photostability of organic fluorescent dyes and to develop and evaluate a route of their derived polymeric fluorescent dyes.

A series of novel polymeric fluorescent dyes were prepared using 3-(2-benzimidazolyl)-7-(diethylamino)-coumarin (disperse yellow 8GFF, abbreviated as 8GFF) and polyethylene glycol (PEG) as raw materials. First, an intermediate of carboxyl functioned 8GFF was prepared by condensation reaction of 8GFF and pyromellitic dianhydride; and then the polymeric fluorescent dyes were synthesized by reacting PEG with the condensate intermediate.

FTIR, UV-vis, and PL showed that the polymeric fluorescent dyes had been successfully synthesised, and the photostability of organic fluorescent dyes was improved significantly.

In the present work, the polymeric fluorescent dyes had been successfully synthesized, and the photostability of organic fluorescent dyes was improved significantly. This methodology can be employed to prepare novel polymeric fluorescent materials and to improve the photostability of organic dyes for various applications.

Polycondensable dyes offer a new area of material science which can be widely used in coloured polymer materials production.

The method developed in the study reported in this paper provided a new strategy to develop new types of polycondensable dyes materials with fluorescent property.

The purpose of this study is to prepare new pigments derived from Red Lake C (RLC) to be applied in the inks industry and to identify their chemical nature, as well as their physical properties.

A number of pigments that could be applied in special printing were prepared via the reactions of RLC with appropriate Ni(II) and Zn(II) salts in aqueous and ethanolic solutions. The obtained pigments were prepared as solid compounds and characterized using different instrumental analysis such as Ultraviolet-Visible, Fourier Transform Infrared Spectroscopy, ¹H NMR spectra and magnetic measurements. The physical properties of these pigments were investigated using “American Standard Testing Methods” (ASTM). After that, the pigments were applied in ink formulations to test their performance and open the way to their real applications in the printing inks industry.

The results of this work revealed that the performance of the new prepared pigments is closer to the performance of the commercial pigments which are already used in ink industry.

Red lake C, as well as the new pigments, can be applied in other different industries such as coated papers, crayons, rubber and baking enamels.

The prepared pigments will be economically feasible and a good alternative to the original expensive commercial pigments which are already used in the inks industry.

In this work, the authors used reversible addition-fragmentation transfer (RAFT) polymerization to develop a new cationic acrylate modified epoxy resin emulsion for water-borne inkjet which have the advantages of both polyacrylate and epoxy resin. The emulsion was successfully used in the canvas coating for inkjet printing. This paper aims to contribute to the development of novel cationic emulsions for inkjet printing industry.

In this work, the epoxy acrylate was synthesized from RAFT agent and epoxy resin firstly. Cationic macromolecular emulsifier was prepared by RAFT polymerization, using 2,2’-Azobisisobutyronitrile as initiator, 2-(dimethylamino)ethyl methacrylate and styrene as monomer, which was directly used to prepare the emulsion. The influences of the amount of 2-(dimethylamino)ethyl methacrylate on particle size, zeta potential and water contact angle were studied. Finally, the cationic emulsion was used to print images by inkjet printing.

The emulsion has the smallest particle size, the highest potential and the highest water contact angle when the DM content is 13 Wt.%. The transmission electron microscopy analysis reveals the latex particles is core-shell sphere with the diameters in the range 120–200 nm. The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

The aim of this paper is to describe the preparation and characterisation of poly(methyl methacrylate) (PMMA) (Mw: 996,000) and dammar mixtures to obtain a new series of natural coating materials for application on mild steel substrates. Dammar is a natural resin extracted from Dipterocarpus Grandiflorus sp., or kruing trees, which grow mainly in the tropical Asia Pacific forest.

Natural dammar resin was mixed with PMMA at different weight percentages in xylene as a solvent and dammar as dominant component. The mixtures were applied on mild steel Q‐panels to form dry coating films. The coating films were investigated under Attenuated Total Reflection‐Fourier Transforms Infrared (ATR‐FTIR) technique to observe the presence of functional groups from PMMA and dammar. Resistivity of coating films against corrosive agents from electrolytes was measured by using potential time measurement (PTM) technique. ASTM D3359 (cross‐hatch) technique was used to measure the coating film adhesion strength on the substrate. The entire tests were conducted at 28°C.

Natural dammar resins is potentially applicable for coating on cold rolled mild steel Q‐panel when mixed with PMMA. Blended dammar resin with PMMA in 5:5 ratio (coded as DP50) was found to give the highest energy of rapid impact indenter. Cross‐hatch test under ASTM D3359 revealed that 50 percent w/w of dammar in PMMA had increased the adhesion strength of the coating film where there was no coating area peeling off from the substrate after the test. DP50 also had the longest time to resist penetration of electrolytes through the coating film when immersed in salt water.

Decreasing the amount of dammar lower than 50 percent weight ratio with PMMA will cause high viscosity and inhomogeneous mixtures.

Natural dammar resin mixed with PMMA (behaviour naturally in free standing film) for coating paint application was formulated.