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Phenolic epoxy vinyl ester resin (PEVER) is an advanced resin matrix, which has excellent heat resistance, electrical insulation. However, the brittleness and poor toughness of its curing product limited its application, so this paper aims to modify the PEVER with hyperbranched polyimide (HBPI), so as to enhance the toughness, heat resistance and dielectric properties of PEVER.

Hexamethylene diisocyanate trimer was used as the central reactant. Methyl tetrahydrophthalic anhydride was used as the branching unit, stannous octoate was used as the catalyst and hydroquinone was prepared as the inhibitor. Then, the hyperbranched structure of HBPI was characterized by Fourier transform infrared spectrometer and ¹³C-NMR. Next, PEVER was mixed with different contents of HBPI, and then the authors tested its curing product.

It is found that with the addition of HBPI, the free volume of the system was increased and the content of polar groups was decreased in each unit space, so the dielectric constant (ε) and the dielectric loss (tanδ) were decreased. In addition, PEVER could be well toughened by HBPI and the thermal stability of PEVER was improved.

HBPI has excellent heat resistance. The addition of hyperbranched polymer increases the free volume of the system so it can slow down the transfer of stress and its nearly circular structure can absorb the impact energy from all directions. Moreover, an appropriate amount of free volume can decrease the dielectric constant of PEVER by reducing the content of polar groups.

The purpose of this paper is to show how to remove some dyestuffs, as pollutants, from their aqueous solutions.

To achieve the goal, a water soluble hyperbranched poly (ester‐amide) (HBP) was synthesised using the melt polycondensation method by the reaction of maleic anhydride (MA) and diisopropanol amine (DIPA) at 140°C at a molar ratio of 1:1.3 MA: DIPA, respectively. This HBP was incorporated in the preparation of an effective microcrystalline cellulose (MCC)/dimethyloldihydroxyethylene urea (DMDHEU)/HBP adduct by crosslinking HBP with DMDHEU in presence of MCC. Furthermore, the prepared adduct was characterised by investigation its infra red and then utilised in the removal of three anionic dyestuffs from aqueous solutions, namely Irgalan Blau 3GL (an acid dye), SIRIUS Blau S‐BRR (a direct dye) and Levafix Brill Orange P‐GR (a hydrolysed reactive dye).

The results obtained revealed that the optimum conditions for preparing MCC/DMDHEU/HBP adduct are [HBP], 90 g/l; [DMDHEU], 200 g/l; LR, 1/3.3; [NC₄LH], 20 g/l; a time of 30 min and a temperature of 160°C. Moreover, the results also showed that the extent of removal of such dyestuffs from their aqueous solutions by the prepared adduct follows the order: reactive dye>acid dye>direct dye, it is more pronounced at lower than at higher pH values and the removal of each dye by that adduct follows a first‐order reaction.

Other substrates such as chitosan can be used to prepare more effective adducts.

Hyperbranched polymers can be used effectively to prepare ion exchangers capable of removing the pollutants of dyestuffs from their aqueous solutions.

The aforementioned prepared HBP is a novel hyperbranched polymer and could be applied in the removal of many other pollutants.

The purpose of this paper was to protect carbon steel from corrosion with self–aggregated, eco-friendly, water-soluble hyperbranched polyamide-ester (Hb-PAE).

Hb-PAE was synthesized through bulk polycondensation reaction between maleic anhydride and di-isopropanol amine. Complete structural analysis for the obtained polymer was performed using Fourier Transfer Infra-Red Spectroscopy, 1H NMR, Thermal gravimetric analysis (TGA) and differential scanning calorimetry, and the molar mass was measured using gel permeation chromatography/refractive index. For this study, the surface activity of Hb-PAE with hydroxyl end groups was investigated. Surface tension of 1.0 × 10−6 to 0.1M of both Hb-PAE/H₂O and Hb-PAE/1N HCl systems was measured, and the critical aggregation concentration (CAC) in both systems was determined. Hb-PAE was examined as a corrosion inhibitor for plain carbon steel in both neutral (distilled water) and acidic (1N HCl) media. The corrosion of the steel was studied quantitatively by measuring its weight loss in both media in the absence and presence of Hb-PAE. The surface morphology of the exposed steel test samples was examined using scanning electron microscopy.

It was found that Hb-PAE inhibited corrosion of steel around the CAC, and its corrosion inhibition efficiency was increased by increasing its concentration.

The research can provide a reference for the relationship between the aggregation concentration of the prepared Hb-PAE with its corrosion inhibition efficiency on plain carbon steel. Hb-PAE as a corrosion inhibitor is environmentally acceptable, economical and readily available.

This paper aims to a newly designed photoresponsive four-armed graft copolymer was synthesised and characterised. The synthesised polymer contains photochemical group and a greater part of the cross-linkable functional group which is not affected by short wavelength when subject to under ultraviolet (UV) irradiation in film status.

The four-armed macroinitiator was prepared by reacting diethanol amine with poly [methyl-2-chloro-4-{7-(chloroacetyl) oxy]-2-oxo-2H-chromen-4-yl}-2-methylbutanoate] and acylating the product with chloroacetyl chloride. A grafting reaction with n-butyl methacrylate was carried out in the presence of the four-armed macroinitiator and the catalyst CuBr/2, 2′-bipyridyne at 90°C. All of the synthesised polymers were structurally characterised by Fourier transform infrared spectroscopy (FT-IR) and Hydrogen-1 Nuclear Magnetic Resonance (1H-NMR) spectra. Gel permeation chromatography was used to obtain the molecular weights of polymer.

1H-NMR, FT-IR and ultraviolet-visible (UV-Vis) spectroscopy demonstrated that the four-armed macroinitiator and the graft copolymer was successfully synthesised. The end-functionalised poly(methyl methacrylate) with 7-hydroxyl-4-chloromethyl coumarin was irradiated at the wavelength larger than 300 nm to create the cyclobutane ring in between the 7-hydroxyl-4-chloro methyl coumarin unities. To characterise the polymer and show the transformation of coumarin unities into photodimers, 1H-NMR, FT-IR and UV-Vis spectroscopy were used.

Graft copolymer containing coumarin has involves photocrosslinkable functional group, in which reactive functional group has attracted great interest from both industrial and academic fields. Their synthesis provides the opportunity for a compatible modification of the graft copolymer structure to develop adapted macromolecules for a range of end practices.

A photoresponsive graft copolymer can have a role in an active area of polymer chemistry research due to its uses in the areas of photolithography, liquid crystal, non-linear optical materials, laser dyes, fluorescence materials and future microelectronics.

Graft copolymers containing a photocrosslinkable functional group, and a star polymer may be prepared using the method described in this paper and then used in technological applications. The method discussed here also allows photoinduced reversible self-healing in solid polymers.

The purpose of this investigation was to develop sustainable resource-based anticorrosive coating material using Pongamia glabra seed oil and tannic acid (TA), as well as to improve the coating properties.

TA-modified fatty amide diol was synthesized by condensation polymerization. First, Pongamia glabra seed oil was converted to fatty amide diol (Pongamia oil fatty amide, PFA) that was further modified by TA with different parts per hundred of resin (10, 15 and 20) to develop a polyether fatty amide (PFA-TA). The confirmation of reaction between TA and PFA was carried out using Fourier transform infrared spectroscopy. The thermal behavior of PFA-TA was studied by thermogravimetric analyses. Coatings of several PFA-TA resins were applied to steel (i.e. plain carbon steel) coupons to investigate their physico-mechanical and anticorrosive performance. The corrosion protection performance was observed using AC impedance and polarization tests.

TA-modified fatty amide coatings showed the highest scratch hardness of 2.5 kg, flexibility (1/8 inch) and gloss at 45° was 60-62. Among all compositions, PFA-TA15 showed the best physico-mechanical and anticorrosion performance. Corrosion tests of coated panels were examined in different corrosive media (3.5 wt per cent HCl, 3.5 wt per cent NaOH and 5.0 wt per cent NaCl) using potentiodynamic polarization and AC impedance measurements. PFA-TA may find application as an eco-friendly protective coating, and thermal analyses revealed that it can be safely used up to 300°C.

This paper provides the development of protective coatings for steel from non-edible seed oil and TA to utilize sustainable resources.

This article aims to present a systematic and up-to-date account of carbon-based reinforcements, including carbon nanotube (CNT), carbon nanofibre (CNF), carbon black (CB), carbon fibre (CF) and grapheme, in shape-memory polymer (SMP) for electrical actuation.

Studies exploring carbon-based reinforcement in SMP composites for electrically conductive performance and Joule heating triggered shape recovery have been included, especially for the principle design, characterisation and shape recovery behaviour, making the article a comprehensive account of the systemic progress in SMP composite incorporating conductive carbon reinforcement.

SMPs are fascinating materials and have attracted great academic and industrial attention owing to their significant macroscopic shape deformation in the presence of an appropriate stimulus. The working mechanisms, the physico requirements and the theoretical origins of the different types of carbon-based reinforcement SMP composites have been discussed. Current research and development on the fabrication strategies of carbon-based reinforcement SMP composites have been summarised.

A systematic review is to evaluate carbon-based reinforcements in SMPs for electrical actuation and discuss recent developments and future applications.

Carbon-based reinforcements in SMPs can be used as smart deployable space structure in the broad field of aerospace technologies.

To reveal the research and development of utilising CNT, CNF, CB, CF and grapheme to achieve shape recovery of SMP composites through electrically resistive heating, which will significantly benefit the research and development of smart materials and systems.