Development and characterization of bio-composites using senegalia catechu resin

Owing to the increase in demand on bio-degradable materials, the present researches focus on the development of materials with full degradability. This research is intended to develop a bio-resin–based composite from senegalia catechu gum for light load automotive applications. The bio-resin obtained from the plant is processed with commercial polyester in order to make it as a functional resin for composite preparation. The synthesized resin is made in the form of structural materials by adding jute reinforcements in varying proportions. An extensive study on the various characters in comparison with the synthetic resin–based composites has been done which includes mechanical strengths analysis and thermal characters investigation. It is revealed that the bio-resin–based composites are good against tensile, flexural and impact loads as compared to that of the synthetic resin composites. In addition, it has been witnessed that the material with 40% weight of jute fabric is apt for offering highest resistance against tensile, flexural and impact loads. Micro-structural investigations proved that the bio-resin–based composites are superior in reducing the flaws and enhancing the bonding of resin with fibres as compared to that of the synthetic resin-based composites. Further, the thermal characterization showed that the bio-resin–based composites have high thermal stability as compared to the synthetic composites, and hence, a positive sign is obtained for bio-resin–based composites in both mechanical and thermal characters.

Causes of Blistering in Plastic Coatings on Screeds and Concrete

In the course of repairs or upgrading measures, it is often necessary to provide floors with synthetic resin coatings. After the work has been carried out, bubbles may form. The article lists the various mechanisms that cause blistering (osmotic pressure, impurities in the aggregate of the screed or concrete, chemical reactions, e.g. alkali silica reaction). By aid of a case study, the procedure for determining the causes of blistering is given in more detail. The investigations have shown that the formation of bubbles was due to alkali-silica reactions of opal sandstone particles in the screed.

Basic Experimental Studies on Coconut Shell Charcoal Ash in Modified Bitumen

For reducing the cost in bitumen roads and also increasing the efficiency of bituminuous roads, varieties of materials are used for improving the road by using coconut shell charcoal ash as fillers in the flexible pavement. In the literature work, the main descriptive of the work is to compare the results with different percentages of coconut shell charcoal ash in bitumen. The Properties of the coconut shell charcoal possesses are resistance to breaking the materials, absorbing the heat, moisture content of surface, grading, heating and synthetic resin glues which is important for pavement of bitumen roads. Therefore, its stability of Marshall stability test and flow value in Marshall stability and air void ratio are obtained. So that it can be compared with different modified percentage as 4.5%, 5%, 5.5% and 6% in test on Bitumen. From this test we can establish so that it can be useful as a substitute as a coconut shell charcoal ash for improving the strength, quality and durability of bitumnious road. For carrying out these experiments, Marshall stability test is used for obtaining better results for normal mix and modified mix for the bitumen.

Enantioselective Resolution of (R, S)-DMPM by a Adsorption-Covalent Crosslinked Esterase PAE07 from Pseudochrobactrum Asaccharolyticum WZZ003

(R)-N-(2,6-dimethylphenyl) alanine ((R)-MAP-acid) is an important chiral intermediate of the Fungicide (R)-Metalaxyl. In this study, ten kinds of immobilized resins(XAD1180N, H103, HAD7HP, D3520, NKA, D101 , DM11,850 JinKai, Primary amino resin and 850 synthetic resin) were used to adsorption-covalent crosslinked esterase PAE07 for splitting (R, S)-DMPM. The resin D3520 with porous structure and hydrophobic polystyrene was selected for immobilization as the carrier, after optimization of the immobilization conditions, the enzyme load is 20:1 (mg/g), the adsorption time is 4h, and the adsorption buffer pH is 7.0 . The Km and Vmax of the free esterases were 35.66 mM and 4.46 mM/mg·min, respectively, The Km and Vmax of the immobilized PAE07 were 19.05 mM and 2.84 mM/mg·min. The SEM analysis showed that the immobilized esterase PAE07 had higher thermal stability, pH stability and substrate specifity than those from the free esterase. Under the optimal conditions,the reaction was carried out at 35°C and 200 rpm for resolution of 350 mM substrate for 14 hours, the conversion rate reached 48%, and the e.e.p was 99.5%.The repeatability of immobilized esterase PAE07 was evaluated by continuous catalytic resolution of (R, S)-DMPM. The results showed that after 15 times of repeated use, 86.2% of the relative enzyme activity was retained. These results proved that immobilized esterase PAE07 as a new catalyst had great potential for the application and industrial enzymatic resolution of (R, S)-DMPM to prepare (R)-metalaxyl.

UV polymerization and property analysis of maleacylated methyl cellulose acrylic acid absorbent resin

In this paper, maleic anhydride (MA) was grafted onto methyl cellulose (MC) and then reacted with acrylic acid to synthesize a high gel strength and fast water absorption resin (AA-co-MC-g-MA) by UV polymerization. The reaction conditions of maleylated methylcellulose (MC-g-MA) were investigated, including the ratio of MC to MA, reaction time and catalyst amount. In addition, the reaction conditions for the synthesis of super absorbent resin were as follows: the amount of MC-g-MA, the degree of substitution of MC-g-MA, polymerization time, and the amount of initiator. Under optimal conditions, the maximum water absorption volume of synthetic resin was 2116 g/g, and the maximum salt absorption rate was 139 g/g. The water absorption resin prepared this time had high water absorption, water retention, excellent pH sensitivity, etc. It was hoped that it will have a good application prospect in the field of industrial production and agriculture in the future.

A Novel and Simpler Alkaline Hydrolysis Methodology for Extraction of Ferulic Acid from Brewer’s Spent Grain and its (Partial) Purification through Adsorption in a Synthetic Resin

This work aims to develop simpler methodologies of extracting ferulic acid (FA) from brewer’s spent grain (BSG). BSG is produced by brewing companies at high amounts all over the year and does not possess a direct application. Thus, its use as raw material for extraction of bioactive compounds has gained attention in the last years. FA has different interesting applications in cosmetics, food industry, and pharmaceutics. Several studies aim for its extraction from BSG by various methods, namely alkaline hydrolysis. In the present work, we suggest the use of autoclave to process higher amounts of BSG in a lab scale. A simplification of the regular post-hydrolysis procedures is also proposed to decrease the number of experimental steps and energy costs and to simultaneously increase the extraction yield (up to 470 mg of FA per 100 g of BSG). The adsorption of extracted FA in a synthetic resin is suggested as a partial purification method.