The utilisation of latex reclaim rubber in natural rubber

Scrap latex products contain rubber hydrocarbon of very high quality, that is only slightly crosslinked. A novel economic technique for converting such latex waste into a processible material is developed. This paper reports the effect of adding this latex reclaim to natural rubber. It is shown that latex reclaim can replace raw natural rubber up to about 50 wt.% without affecting mechanical properties.

Studies on Latex Reclaim and its Blends

The primary aim of this work has been to develop a cost effective process that can be operated at room temperature for developing latex reclaim with superior mechanical properties. With this objective in mind the researcher proposes to study the reclaiming action of four different chemicals on latex products waste. Waste latex products are chosen because it has a higher potential to generate good quality rubber hydrocarbon since all latex products are based on either high quality concentrated latex or creamed latex. Moreover, all latex products are only lightly crosslinked and not masticated and hence not mechanically degraded. The author also proposes to fully explore the possible application of latex reclaim in various fields..

Production of latex reclaim and its utilisation in polymer blends

The overall objective of the present study was to develop a novel and economic reclaiming process that does not adversely affect the quality of rubber and to investigate methods of utilising the reclaim. Since waste latex products represent a potential source of high quality rubber hydrocarbon, it was decided to develop a process based on such latex wastes. The study revealed that latex reclaim could replace raw natural rubber upto about 50 per cent of its weight without any serious deterioration in mechanical properties.

The Utilization of Waste Latex Products in Styrene-Butadiene Rubber

Waste latex products are converted to a processabto material by a novel economical process developed in our laboratory , It contains rubber hydrocarbon of very high quality and Is lightly cross -linked. Styrene-butadlene rubber is mixed with latex reclaim In different proportions . The mechanical properties are found to be improved up to 60 percent replacement of styrene-butadlene rubber by latex reclaim . The curing of styrene-butadiene rubber Is found to be accelerated by the addition of latex reclaim. The processablllty study shows that the blends can be processed similar to SBRINR blends.

STUDIES ON THE CELL STRUCTURE AND MECHANICAL PROPERTIES OF NR/LATEX RECLAIM/HSR BASED MICROCELLULAR SHEETS

In natural rubber/high styrene resin microcellular sheets, part of natural rubber was replaced by latex reclaim prepared from waste latex products. The mechanical properties and cell structure of the products were evaluated. It was found that latex reclaim can replace about 30% of natural rubber without affecting the technical properties of the microcellular sheets.

Rheological and Extrudate Behaviour of Natural RubberlLatexReclaim Blends

ABSTRACT: The rheological and extrudate behaviour of natural rubber/latex reclaim blends were evaluated using a capillary viscometer . The study shows that the viscosity of natural rubber decreases marginally on the addition of latex reclaim while the variation of viscosity with shear rate is not affected. The temperature sensitivity of the blends is not affected significantly with the addition of latex reclaim . The extrudates of natural rubber/latex reclaim blends are smooth up to the addition of about 50 wt. percent latex reclaim in filled natural rubber compounds.

OPTIMAL UTILIZATION OF SERVICE FACILITY FOR A k-OUT-OF-n SYSTEM WITH REPAIR BY EXTENDING SERVICE TO EXTERNAL CUSTOMERS IN A RETRIAL QUEUE

In this paper, we study a k-out-of-n system with single server who provides service to external customers also. The system consists of two parts:(i) a main queue consisting of customers (failed components of the k-out-of-n system) and (ii) a pool (of finite capacity M) of external customers together with an orbit for external customers who find the pool full. An external customer who finds the pool full on arrival, joins the orbit with probability and with probability 1− leaves the system forever. An orbital customer, who finds the pool full, at an epoch of repeated attempt, returns to orbit with probability (< 1) and with probability 1 − leaves the system forever. We compute the steady state system size probability. Several performance measures are computed, numerical illustrations are provided.

Studies on the Utilisation of Rubber Reclaim in Elastomers

The thesis describes utilisation of reclaimed rubber, Whole Tyre Reclaim (WTR) produced from bio non- degradable solid pollutant scrap and used tyres. In this study an attempt has made to optimize the substitution of virgin rubber with WTR in both natural and synthetic rubber compounds without seriously compromising the important mechanical properties. The WTR is used as potent source of rubber hydrocarbon and carbon black filler. Apart from natural rubber (NR), Butadiene rubber (BR), Styrene butadiene rubber (SBR), Acrylonitrile butadiene rubber (NBR) and Chloroprene rubber (CR) were selected for study, being the most widely used general purpose and specialty rubbers. The compatibility problem was addressed by functionalisation of WTR with maleic anhydride and by using a coupling agent Si69.The blends were systematically evaluated with respect to various mechanical properties. The thermogravimetric analyses were also carried out to evaluate the thermal stability of the blends.Mechanical properties of the blends were property and matrix dependant. Presence of reinforcing carbon black filler and curatives in the reclaimed rubber improved the mechanical properties with the exception of some of the elastic properties like heat build up, resilience, compression set. When WTR was blended with natural rubber and synthetic rubbers, as the concentration of the low molecular weight, depolymerised WfR was increased above 46-weight percent, the properties deteriorates.When WTR was blended with crystallizing rubbers such as natural rubber and chloroprene rubber, properties like tensile strength, ultimate elongation were decreased in presence of WTR. Where as in the case of blends of WTR with non-crystallizing rubbers reinforcement effect was more prominent.The effect of functionalisation and coupling agent was studied in three matrices having different levels of polarity(NBR, CR and SBR).The grafting of maleic anhydride on to WTR definitely improved the properties of its blends with NBR, CR and SBR, the effect being prominent in Chloroprene rubber.Improvement in properties of these blends could also achieved by using a coupling agent Si69. With this there is apparent plasticizing effect at higher loading of the coupling agent. The optimum concentration of Si69 was 1 phr for improved properties, though the improvements are not as significant as in the case of maleic anhydride grafting.Thermal stability of the blend was increased by using silane-coupling agent.

Application of Fermentation Techniques in the Utilization of Prawn Shell Waste

The present study aimed at the utlisation of microbial organisms for the production of good quality chitin and chitosan. The three strains used for the study were Lactobacillus plantarum, Lactobacililus brevis and Bacillus subtilis. These strains were selected on the basis of their acid producing ability to reduce the pH of the fermenting substrates to prevent spoilage and thus caused demineralisation of the shell. Besides, the proteolytic enzymes in these strains acted on proteinaceous covering of shrimp and thus caused deprotenisation of shrimp shell waste. Thus the two processes involved in chitin production can be affected to certain extent using bacterial fermentation of shrimp shell.Optimization parameters like fermentation period, quantity of inoculum, type of sugar, concentration of sugar etc. for fermentation with three different strains were studied. For these, parameters like pH, Total titrable acidity (TTA), changes in sugar concentration, changes in microbial count, sensory changes etc. were studied.Fermentation study with Lactobacillus plantarum was continued with 20% w/v jaggery broth for 15 days. The inoculum prepared yislded a cell concentration of approximately 108 CFU/ml. In the present study, lactic acid and dilute hydrochloric acid were used for initial pH adjustment because; without adjusting the initial pH, it took more than 5 hours for the lactic acid bacteria to convert glucose to lactic acid and during this delay spoilage occurred due to putrefying enzymes active at neutral or higher pH. During the fermentation study, pH first decreased in correspondence with increase in TTA values. This showed a clear indication of acid production by the strain. This trend continued till their proteolytic activity showed an increasing trend. When the available sugar source started depleting, proteolytic activity also decreased and pH increased. This was clearly reflected in the sensory evaluation results. Lactic acid treated samples showed greater extent of demineralization and deprotenisation at the end of fermentation study than hydrochloric acid treated samples. It can be due to the effect of strong hydrochloric acid on the initial microbial count, which directly affects the fermentation process. At the end of fermentation, about 76.5% of ash was removed in lactic acid treated samples and 71.8% in hydrochloric acid treated samples; 72.8% of proteins in lactic acid treated samples and 70.6% in hydrochloric acid treated samples.The residual protein and ash in the fermented residue were reduced to permissible limit by treatment with 0.8N HCI and 1M NaOH. Characteristics of chitin like chitin content, ash content, protein content, % of N- acetylation etc. were studied. Quality characteristics like viscosity, degree of deacetylation and molecular weight of chitosan prepared were also compared. The chitosan samples prepared from lactic acid treated showed high viscosity than HCI treated samples. But degree of deacetylation is more in HCI treated samples than lactic acid treated ones. Characteristics of protein liquor obtained like its biogenic composition, amino acid composition, total volatile base nitrogen, alpha amino nitrogen etc. also were studied to find out its suitability as animal feed supplement.Optimization of fermentation parameters for Lactobacillus brevis fermentation study was also conducted and parameters were standardized. Then detailed fermentation study was done in 20%wlv jaggery broth for 17 days. Also the effect of two different acid treatments (mild HCI and lactic acid) used for initial pH adjustment on chitin production were also studied. In this study also trend of changes in pH. changes in sugar concentration ,microbial count changes were similar to Lactobacillus plantarum studies. At the end of fermentation, residual protein in the samples were only 32.48% in HCI treated samples and 31.85% in lactic acid treated samples. The residual ash content was about 33.68% in HCI treated ones and 32.52% in lactic acid treated ones. The fermented residue was converted to chitin with good characteristics by treatment with 1.2MNaOH and 1NHCI.Characteristics of chitin samples prepared were studied and extent of Nacetylation was about 84% in HCI treated chitin and 85%in lactic acid treated ones assessed from FTIR spectrum. Chitosan was prepared from these samples by usual chemical method and its extent of solubility, degree of deacetylation, viscosity and molecular weight etc were studied. The values of viscosity and molecular weight of the samples prepared were comparatively less than the chitosan prepared by Lactobacillus plantarum fermentation. Characteristics of protein liquor obtained were analyzed to determine its quality and is suitability as animal feed supplement.Another strain used for the study was Bacillus subtilis and fermentation was carried out in 20%w/v jaggery broth for 15 days. It was found that Bacillus subtilis was more efficient than other Lactobacillus species for deprotenisation and demineralization. This was mainly due to the difference in the proteolytic nature of the strains. About 84% of protein and 72% of ash were removed at the end of fermentation. Considering the statistical significance (Pof demineralization and deproteinisation, we have taken 0.8N HCI for the demineralization study and 0.6M NaOH for deprotenisation study. Properties of chitin and chitosan prepared were analyzed and studied.

Studies on the utilization of selected species of Sharks

This thesis Entitled Studies on the Utilization of selected Species of sharks. The present study is the result of work carried out for 5 years, during the period from April, 1983 to March 1988. The materials were collected from the catches of the Government of India vessels, operated along the south west coast of India and landed in the Integrated Fisheries Project, Cochin—16. The sharks were caught by different types of gears such as bottom trawls, pelagic trawls, long line etc. A number of species of sharks were landed during this period and three species were selected for the present study namely Scoliodon palasorra (bleeker 1853, grey Shark), Carcharhinus limbatus (valenciennes 1839,black tip shark ) and centrophorus granulosus (bloch and schneider 1801 ,spiny shark). During this study period the quantity of shark utilized was 12,55,942 kg out of which 9.71% used for the production of Dressed shark; 36.21% for the production of Fillets; 49.09% converted into Dried shark and 4.99% was domesticallyy marketed as whole form. Besides this 526 kg of dried shark fin and 289.25 kg of shark fin rays were produced.The effect of Smoking of shark fillets and minced meat at different temperature were also studied during this period. Canning of cooked shark meat, smoked fillets and fish balls were carried out in media like brine, vegetable oil, tomato sauce etc. The quality of smoked fillets in vegetable oil was found superior to other canned products from shark meat.During this study an attempt was also made to evaluate the commercial processing of shark resources and found feasible.

Utilization of rice by-products in rubber

The thesis consists of seven chapters. The first chapter is a general introduction on rice by-products, their composition and utilization at present. The different milling processes adopted in paddy and the major by-products obtained from these processes viz. rice husk, rice bran, rice bran oil and rice husk ash are described. The physical properties and chemical composition of the rice husk and its general uses are given in detail. The chemical composition of the rice bran and its separation from paddy is also included. The details of solvent extraction process used for obtaining rice bran oil and also its chemical constitution is discussed in this chapter. Also described is the preparation and the different uses of rice husk ash. A literature survey is also done on the utilization of rice by-products in rubber and plastics as on today. The scope and objectives of the present study is also included at the end of this chapter.

Rashtriya Swasthya Bhima Yojana-Comprehensive Health Insurance Scheme (Rsby-Chis) In Kerala: A Study On The Effectiveness And Utilization Of The Scheme With Special Reference To Ernakulam And Wayanad Districts

Health insurance has become a necessity for the common man, next to food, clothing and shelter. The financing of health expense is either catastrophic or sometimes even frequently contracted illnesses, is a major cause of mental agony for the common man. The cost of care may sometimes result in the complete erosion of the family savings or may even lead to indebtedness as many studies on causes of rural indebtedness bear testimony (Jayalakshmi, 2006). A suitable cover by way of health insurance is all that is required to cope with such situations. Health care insurance rightly provides the mechanism for both individuals and families to mitigate the financial burden of medical expenses in the present context. Hence a well designed affordable health insurance policy is the need of the hour.Therefore, it is very significant to study the extent to which the beneficiaries in Kerala make use of the benefits provided by a social health insurance scheme like RSBY-CHIS. Based on the above pertinent points, this study assumes national relevance even though the geographical area of the study is limited to two districts of Kerala. The findings of the study will bring forth valuable inputs on the services availed by the beneficiaries of RSBYCHIS and take appropriate measures to improve the effectiveness of the scheme whereby maximum quality benefit could be availed by the poorest of the poor and develop the scheme as a real dawn of the new era of health for them

“Studies on extracellular enzyme production during growth of Pleurotus sp. on lignocellulosic agriwaste and the utilization of spent mushroom substrate”

Commercially, Pleurotus spp. of mushroom are cultivated in bags. After mushroom cultivation, spent substrate remains as residual material. Proper recycling of spent substrate is beneficial for our economy. Spent substrate can be utilized for various other value added purposes through the proper knowledge of its components. Composition of various components depends on the activity of extracellular enzymes in the spent substrate. The present study was conducted to know the enzyme profile of some major extracellular enzymes - cellulase, hemicellulase (xylanase), pectinase and ligninase (lignin peroxidase and laccase) and to estimate cellulose, hemicellulose, pectin and lignin in the substrate. The use of spent substrate as a source of fibre and ethanol, and in the biodegradation of phenol by Pleurotus spp. was also investigated

Pilot Plant Studies On The Utilization Of Industrial Wastes For Industrial Bitumen Manufacture

The main objectives of the investigations reported in the present thesis are the following: (1) to find out some industrial wastes as cheaper additives to augment the air-blowing polymerization process of bitumen. This will bring down the cost of production of industrial bitumen which can be applied for the manufacture of bitumenous paints, roofing and flooring materials etc. (2) to find out suitable promoters for the above additives. This will bring down the consumption of the additives (3) to help in the industrial pollution control (4) to investigate the usefulness of the industrial bitumen produced in the production of bituminous paints (5) to find out thekinetic parameters of the reactions invovled with different additives. This is essential for the design, construction and operation of new industrial bitumen plants using the additives investigated. This will also enable us to establish the mechanism of the reactions involved in the process

Utilization of prawn waste for chitinase production by the marine fungus Beauveria bassiana by solid state fermentation

Prawn waste, a chitinous solid waste of the shell®sh processing industry, was used as a substrate for chitinase production by the marine fungus Beauveria bassiana BTMF S10, in a solid state fermentation (SSF) culture. The process parameters in¯uencing SSF were optimized. A maximum chitinase yield of 248.0 units/g initial dry substrate (U/gIDS) was obtained in a medium containing a 5:1 ratio (w/v) of prawn waste/sea water, 1% (w/w) NaCl, 2.5% (w/w) KH2PO4, 425±600 lm substrate particle size at 27 °C, initial pH 9.5, and after 5 days of incubation. The presence of yeast extract reduced chitinase yield. The results indicate scope for the utilization of shell®sh processing (prawn) waste for the industrial production of chitinase by using solid state fermentation.