• Advances in materials Research
• /
• v.11 no.3
• /
• pp.191-209
• /
• 2022

Very slow degradation of synthetic based polymers has created a severe environmental issue that increased awareness towards research in polymers of biodegradable property. Soy protein isolate (SPI) is a natural biopolymer used as matrix in green composites but it has limitations of low mechanical properties and high water sensitivity. To enhance mechanical properties and reduce water sensitivity of Jute-SPI composites, SPI was modified with pine rosin which is also a natural cross-linking agent. 30% glycerol on the weight basis of a matrix was used as a plasticizer. The fibre volume fraction was kept constant at 0.2 whereas the pine rosin in SPI ranged from 5% to 30% of the matrix. The effects of pine rosin on mechanical, thermal, water sensitivity and surface morphology have been characterized using various techniques. The mechanical properties and water absorbency were found to be optimum for 15% pine rosin in Jute-SPI composite. Therefore, Jute-SPI composite without pine rosin and with 15% pine rosin were chosen for investigation through characterization by Fourier transforms infrared spectroscopy (FTIR), Thermo-gravimetric analysis (TGA), X-Ray diffraction (XRD) and Scanning electron microscope (SEM). The surface morphology of the composite was influenced by pine rosin which is shown in the SEM image. TGA measurement showed that the thermal properties improved due to the addition of pine rosin. Antimicrobial test showed antimicrobial property in the composite occurring 15% pine rosin. The research paper concludes that the modification of SPI resin with an optimum percentage of pine rosin enhanced mechanical, thermal as well as water-resistant properties of jute fibre reinforced composites.

• Advances in materials Research
• /
• v.13 no.4
• /
• pp.269-283
• /
• 2024

Biocompositesmade up of starch and jute fibres are biodegradable and environmentally friendly materials for sustainable development. In this study, corn starch has been separately modified with 15% pine rosin and 40% glutaraldehyde, and 30% glycerol is used as a plasticizer. The composites have been prepared for three different volume proportions of matrix and jute fibre such as 60:40, 70:30 and 80:20 by using a hot compression moulding machine. The effects of pine rosin and glutaraldehyde on mechanical properties have been studied. Pine rosin modified starch jute composites have shown higher tensile and flexural properties as compared with glutaraldehyde modified starch jute composite. The highest tensile strength and modulus are found at 60:40 matrix and jute fibre volume proportion of pine rosin modified starch jute composite which are 13.97 MPa and 782.94 MPa respectively. Similar trends were found in flexural strength and modulus for pine rosin modified starch jute composite having matrix to jute fibre proportion 60:40 which are 29.18 MPa and 1107.76 MPa respectively. But, in case of impact strength, glutaraldehyde modified starch jute composite having matrix to jute fibre proportion 80:20 have shown highest impact strength that is 59.05 KJ/m². Starch-jute composite with glutaraldehyde shows 33% more water absorbency as compared to composite having pine rosin as cross linker. Highest FTIR graph indicates that the number of -OH group is much lower in case of pine rosin modified starch than glutatraldehyde modified starch which indicates that bonds formed by pine rosin are much stronger than the bonds formed by glutaraldehyde. The surface morphology of the composite was influenced by pine rosin and glutaraldehyde which is shown in the SEM image.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.6
• /
• pp.476-481
• /
• 2004

The aim of this study was to formulate a sustained release system for indomethacin (IND) with rosin gum obtained from a pine tree. Rosin microparticles were prepared by a disper­sion and dialysis method without the addition of surfactant. In order to investigate the influence of solvents on the formation of colloidal microparitcles, various solvents like ethanol, DMF, DMAc, and acetone were used. The rosin microparticles containing IND were characterized by X­ray differactometry (XRD) and differential scanning calorimetry (DSC). The morphologies of rosin microparticles observed by scanning electron microscopy (SEM) were spherical. The solvents used to dissolve rosin significantly affected the drug content and drug release rate of IND. The release behaviors of IND from the rosin microparticles were dependent on the drug content and size of the particles. Rosin micorparticles with a higher drug content and of a larger particle size had a slower drug release rate. Also, the IND release rate from the rosin microparticles could be regulated by the rosin content in the microparticles. From these results, rosin microparticles have the potential of being used as a sustained release system of IND.

• Journal of the Korean Wood Science and Technology
• /
• v.45 no.4
• /
• pp.409-418
• /
• 2017

This work attempted to manufacture glued-laminated timber (Glulam) bonded with melamine-urea-formaldehyde (MUF) resin adhesives at various melamine contents from 20% to 50% under high frequency (HF) heating for a very short time. Two preparation methods were employed to prepare MUF resin adhesives with different melamine contents: one-batch method of synthesizing MUF resins in a single batch, and two-batch method of mixing urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized separately. As the melamine content increased, the gelation time and peak temperature of MUF resins decreased. The adhesion performance of plywood showed that the one-batch MUF resin adhesive with 50% melamine content only satisfied the standard requirement of water resistance. Thus, the one-batch MUF resin adhesive with 50% melamine content was applied for bonding wood lamina from four softwood species such as Japanese larch, Korean red pine, Korean pine and Japanese cedar to manufacture Glulam under HF heating. All Glulam samples bonded with the one-batch MUF resin adhesives with 50% melamine content except those from Korean Red Pine satisfied the requirement in water soaking or boiling water delamination test as an exterior grade Glulam. The presence of rosin in Korean Red Pine was believed to be responsible for its poor adhesion. These results showed that the one-batch MUF resin adhesives with 50% melamine content provided acceptable water resistance with exterior grade Glulam manufactured under HF heating.

• Journal of the Mineralogical Society of Korea
• /
• v.22 no.2
• /
• pp.107-114
• /
• 2009

In present study, an alternative process for manufacturing ultra marine blue by using kaolin, sulfur, sodium carbonate, silica, and rosin was investigated. From the experiments, it was found in the reductive calcination process that the temperature variation with the bed height of input materials is relatively high due to the inadequate thermal conductivity of them. It was also found that the color of the ultramarine blue manufactured is sensitive for the shape of the input materials and the calcinations conditions, and specially the heating rate is very important to form ultramarine. For manufacturing green ultramarine by using sulfur, sodium carbonate, silicon, and pine resin, an optimum condition was investigated to be the heating rate region below $0.6^{\circ}C/min$, the reaction temperature of $850^{\circ}C$ and the reaction time of 4 hr. At the oxidative calcination process to manufacture ultra marine blue from green ultramarine, the optimum flow rate of air is $500{\sim}550\;{\ell}/kg$ (green ultramarine) and the reaction temperature is $500{\sim}550^{\circ}C$.