Rubber Seed Oil: A Multipurpose Additive in NR and SBR Compounds

ABSTRACT: Rubber seed oil was used as a multipurpose ingredient in natural rubber (NR) and styrene butadiene rubber (SBR) compounds. The study shows that the oil, when substituted for conventional plasticiser, imparts excellent mechanical properties to NR and SBR vulcanizates. Further, it also improves aging resistance, reduces cure time, increases abrasion resistance and flex resistance, and reduces blooming.

A Study on the Use of Castor Oil as Plasticizer in Natural Rubber Compounds

Mechanical properties and thermal degradation of natural rubber compounds containing castor oil were studied to evaluate its suitability as plasticizer. Naphthenic oil was used as a reference plasticizer. The cure time was marginally lower in the case of castor oil mixes, probably due to the presence offree fatty acids in it. The tear strength and modulus were better in the case of mixes containing castor oil, while most of the other mechanical properties were comparable to the mixes containing naphthenic oil. The heat build up and compression set were higher than that of the naphthenic oil mixes. Thermal studies showed an increase of 8 °C in the temperature of initiation of degradation and an increase of 6 °C in the temperature at which the peak rate of degradation occurred. The peak rate of degradation was comparable to that of the reference compound

A Study on the Use of Coconut Oil as Plasticiser in Natural Rubber Compounds

Mechanical properties and thermal degradation characteristics of natural rubber compounds captaining coconut oil were compared with that of a control compound containing naphthenic oil. Cure time was marginally lower in the case of coconut oil mixes, probably due to the presence of free fatty acids. Tensile strength , tear strength, resilience and abrasion resistance were better than the naphthenic oil-based compounds . Compression set and hardness were marginally inferior The coconut oil mixes had a crosslink density comparable to that of the reference compound. Thermal studies showed that the temperature of initiation of degradation was increased by 10°C and the temperature at which the peak rate of degradation occured was increased by 7°C. The peak rate of degradation was compa rable to the control compound.

Fibre optic sensor for the detection of adulterant traces in coconut oil

The design and development of a fibre optic evanescent wave refractometer for the detection of trace amounts of paraffin oil and palm oil in coconut oil is presented. This sensor is based on a side-polished plastic optical fibre. At the sensing region, the cladding and a small portion of the core are removed and the fibre nicely polished. The sensing region is fabricated in such a manner that it sits perfectly within a bent mould. This bending of the sensing region enhances its sensitivity. The oil mixture of different mix ratios is introduced into the sensing region and we observed a sharp decrease in the output intensity. The observed variation in the intensity is found to be linear and the detection limit is 2% (by volume) paraffin oil/palm oil in coconut oil. The resolution of this refractometric sensor is of the order of 10−3. Since coconut oil is consumed in large volumes as edible oil in south India, this fibre optic sensor finds great relevance for the detection of adulterants such as paraffin oil or palm oil which are readily miscible in coconut oil. The advantage of this type of sensor is that it is inexpensive and easy to set up. Another attraction of the side-polished fibre is that only a very small amount of analyte is needed and its response time is only 7 s.

ANALYSIS, MODIFICATION, AND EVALUATION OF THE COLD FLOW PROPERTIES OF VEGETABLE OILS AS BASE OIL FOR INDUSTRIAL LUBRICANTS

Poor cold flow properties of vegetable oils are a major problem preventing the usage of many abundantly available vegetable oils as base stocks for industrial lubricants. The major objective of this research is to improve the cold flow properties of vegetable oils by various techniques like additive addition and different chemical modification processes. Conventional procedure for determining pour point is ASTM D97 method. ASTM D97 method is time consuming and reproducibility of pour point temperatures is poor between laboratories. Differential Scanning Calorimetry (DSC) is a fast, accurate and reproducible method to analyze the thermal activities during cooling/heating of oil. In this work coconut oil has been chosen as representative vegetable oil for the analysis and improvement cold flow properties since it is abundantly available in the tropics and has a very high pour point of 24 °C. DSC is used for the analysis of unmodified and modified vegetable oil. The modified oils (with acceptable pour points) were then subjected to different tests for the valuation of important lubricant properties such as viscometric, tribological (friction and wear properties), oxidative and corrosion properties.A commercial polymethacrylate based PPD was added in different percentages and the pour points were determined in each case. Styrenated phenol(SP) was added in different concentration to coconut oil and each solution was subjected to ASTM D97 test and analysis by DSC. Refined coconut oil and other oils like castor oil, sunflower oil and keranja oil were mixed in different proportions and interesterification procedure was carried out. Interesterification of coconut oil with other vegetable oils was not found to be effective in lowering the pour point of coconut oil as the reduction attained was only to the extent of 2 to 3 °C.Chemical modification by acid catalysed condensation reaction with coconut oil castor oil mixture resulted in significant reduction of pour point (from 24 ºC to -3 ºC). Instead of using triacylglycerols, when their fatty acid derivatives (lauric acid- the major fatty acid content of coconut oil and oleic acid- the major fatty acid constituents of monoand poly- unsaturated vegetable oils like olive oil, sunflower oil etc.) were used for the synthesis , the pour point could be brought down to -42 ºC. FTIR and NMR spectroscopy confirmed the ester structure of the product which is fundamental to the biodegradability of vegetable oils. The tribological performance of the synthesised product with a suitable AW/EP additive was comparable to the commercial SAE20W30 oil. The viscometric properties (viscosity and viscosity index) were also (with out additives) comparable to commercial lubricants. The TGA experiment confirmed the better oxidative performance of the product compared to vegetable oils. The sample passed corrosion test as per ASTM D130 method.

Sol-Gel Mesoporous Silica Aerogels and Bio Hybrids for Functional Applications

The thesis covers a systematic investigation on the synthesis of silica aerogels and microspheres with tailored porosity, at ambient conditions by varying the experimental parameters as well as using organic templates. Organically modified silica-gelatin and silica-chitosan hybrids were developed for the first time using alkylalkoxysilanes such as MTMS and VTMS. Application of novel silica-biopolymer antiwetting coatings on different substrates such as glass, leather and textile is also demonstrated in the thesis.

POPULATION GENETIC STUDIES ON THE OIL SARDINE ( Sardinella longiceps )

The objective of present investigation was to study the population genetic structure of S. longiceps by applying three different basic population genetic techniques such as cytogenetics, non-enzymatic biochemicalgenetics (general protein) and morphomeristics/metrics.

Effects of the Piscicides, Mahua Oil Cake and Croton Seed on the Prawn Culture System

Department of Marine Biology, Microbiology and Biochemistry

BIOCHEMICAL GENETIC STUDIES ON THE OIL SARDINE, Sardinella longiceps (CUVIER AND VALENCIENNES, 1847) FROM SELECTED CENTRES OF THE WEST COAST OF INDIA

The main objective of the present investigation was to study the biochemical genetic variability within the species and genetic structure of its regional populations from west coast. Realising the recent report of occurrence of oil sardine fishery in east coast of India, population samples from Mandapam and Madras were also included in the present investigation. The original data gathered on the population genetics of the species have helped to interpret and evaluate the results objectively. The important conclusions drawn from a detailed discussions on the subject would throw some light on the probable process of problematic fluctuations in the abundance of oil sardine fishery of India. The academic and applied values of present discoveries need not be emphasised. The data used for the doctoral thesis were generated during the ICAR ad-hoc project on the "Population genetic studies on oil sardine, sardinella longiceps to identity distinct genetic stocks", carried out at CMFRI, Cochin during the years, 1988-1991

Polyphenolic Compounds Liberated during Coir Retting in a Bio-reactor: Separation, Characterisation and Possible Applications

School of environmental studies, Cochin University of Science and Technology

Studies on the Bioactive Natural Antioxidants From Oilseeds

Antioxidants are substances that when present at low concentrations compared to that of an oxidisable substrate significantly delays or inhibits oxidation of that substrate in food products or in living systems. Antioxidants are either endogenous to the body or derived from the diet. Several types of synthetic antioxidants like BHT, BHA, TBHQ etc. are also used in the food industry. However, findings and subsequent publicity has fostered significant consumer resistance to the use of synthetic food additives as antioxidants, colourants etc. and therefore food industry is in search of potential natural antioxidants from edible sources.The major dietary sources of antioxidant phytochemicals are cereals, legumes, fruits, vegetables, oilseeds, beverages, spices and herbs. In the present study, we have focused on rice bran and its byproducts. Rice is one of the oldest of food crops and has been a staple food in India from very ancient times. It is also the staple food for about 60% of the world's population. Rice bran is a byproduct of the rice milling industry and is a potential commercial source of a healthy edible oil viz. rice bran oil and a variety of bio-active phytochemicals.Defatted rice bran (DRB), a byproduct of rice bran oil extraction, is also a good source of insoluble dietary fiber, protein, phytic acid, inosito I, vitamin B and a variety of other phytochemicals. Though the antioxidant potential of DRB has been demonstrated, it still remained a relatively unexplored source material, which demanded further investigation especially with regard to its detailed phytochemical profile leading to practical application. The focus of the present investigation therefore has been on DRB primarily to establish its phytochemical status and feasibility of using it as a source of bio-active phytochemicals and natural antioxidants leading to value addition of DRB otherwise used as cattle feed. To gain a better understanding of the value of rice bran as a source of phytochemicals, five popular rice varieties of the region viz. PTB 50, PTB 39, PTB 38, JA Y A, and MO 10 and a wild variety (oryza nivara) that is mainly used for medicinal applications in traditional ayurvedic system were characterized along with commercial samples of rice bran. The present study also explains the feasibility of a process for the extraction, enrichment, and isolation of antioxidant compounds from DRB. The antioxidant potential of the extracts were evaluated both in bulk oils and in food relevant model emulsions, using standard in vitro models. Radical scavenging effects, indicative of possible biological effects, were also evaluated.

Synthesis of Bio-Compatible SPION–based Aqueous Ferrofluids and Evaluation of RadioFrequency Power Loss for Magnetic Hyperthermia

Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc). This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm) exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.

Bioremediation of petroleum sludge through Phytoremediation.Land farming and Microbial enhanced oil separation

The objective of this research is to study the feasibility of bioremediating the oily sludge from a refinery site. Three different methods of waste treatment were tried i.e. phytoremediation, land farming and microbial enhanced oil separation in laboratory scale treatment systems. A multiprocess approach by combination of phytoremediation, biostimulation and microbial enhanced oil separation is also presented. The methods of analysis, experimental procedure, and results are incorporated into five chapters of this thesis entitled "Bioremediation of petroleum sludge through phytoremediation, land farming and microbial enhanced oil separation.