Quality Of Rubber Research Articles

Modal Sosial Sebagai Strategi Pengelolaan Usaha Perkebunan Karet Rakyat

Rubber-people plantation in Banyuasin Regency has been entrenched in the daily life of society. Generally cultivated by small scale farmers (narrow) with traditional systems. In contrast to that cultivated by government / private companies, where the exploitation is done on a large scale with modern technology systems. However, judging by the proportion of the area, the rubber-people plantation still dominates, so the business is worth considering, because it can determine the dynamics of Indonesian cultivation. Research is a qualitative study, and is descriptive. Data analysis using data triangulation method. The results showed that the elements of social capital: First, the trust is seen from the citizens who are members of Gapoktan (farmer group) entrust the result of lead (rubber latex) to the chairman of Gapoktan. This is because every Gapoktan usually make a turn every night to keep the rubber latex that has been frozen tesebut not lost. Members who get shift guard is a citizen who participated in Gapoktan. Second, the network obtained from fellow Gapoktan members (with other Gapoktan), from tauke and from the agricultural service. If a strongly created social network, then strong trust will arise as well. Third, social responsibility can be mutual trust of Gapoktan members, as well as maintaining the quality of rubber products to remain qualified; and fourth, Cooperation requires rules, norms, responsibilities, and mutual trust among community members. Similarly, members of farmer groups can be considered important and most decisive. The results showed that the farmers group considered the element of cooperation considered very important in the formation of social capital. Furthermore, the marketing strategy used is with the auction market. Prior to the auction market, the farmers sell the rubber to the collecting traders in the village, either settling or coming on the day of weighing a certain day, once two weeks according to the farmer's habit. The advantage of auction market is the selling price is much higher than the price outside the auction market, the quality of rubber is very decisive prices, honest scales, all official charges, compared with price differences, low fees for auction operations is not a problem. Then, with the sale of rubber by auction or tender is very helpful to farmers economy to be prosperous as it is today. The development of smallholder estates in Talang Ipuh and Air Senggeris, assisted by the Banyuasin district government in addition to impacting the economic welfare of its people, also has an impact on the environment of both the community and environment in the plantation area.

PEMANFAATAN ASAP CAIR DARI PELEPAH KELAPA SAWIT UNTUK MENINGKATKAN KUALITAS BAHAN OLAH KARET PETANI KARET

An effort in improving field latex quality has been conducted through community service activity for rubber farmers at Dusun Alur Hitam, Sekoci Village, Langkat Regency. The farmers generally use unrecommended coagulant such as fertilizer, extract of mengkudu or fern sap for coagulating their latex that can reduce the quality of rubber. The low quality of field latex, thus in turn reduce its selling price and income of farmers. Liquid smoke produced by pyrolysis of palm frond waste was proposed to be used as latex coagulant. Team of community service has designed and manufactured a pyrolysis reactor for this activity. The pyrolysis process produced brown liquid smoke with pH of 3 and a strong smoke smell. The produced liquid smoke can coagulate latex perfectly with the time needed were 2¢,25ʺ; 3¢,21ʺ and 4¢,29ʺ at the ratio of liquid smoke to latex were 1:10, 1:15 and 1:20 respectively with the use of liquid smoke of 2 mL. The dry rubber content of latex reached 73.48%. Thus, the utilization of smoke liquid can improve the dry rubber content as high 20.48% since the rubber buyer agents only set the dry rubber content of 53%. The elongation at break (EB) of latex was in the range of 165.55% - 286.93%. it is necessary to increase the knowledge and skill of rubber farmers. In the future, the establishment of farmer group or cooperative at Dusun Alur Hitam should be encouraged so as to facilitate the farmers in selling their product

Estimation of the nitrogen concentration of rubber tree using fractional calculus augmented NIR spectra

Natural rubber (Hevea brasiliensis) is a high-valued industrial crop in tropical areas. Reasonable fertilization can improve the quality and production of the natural rubber. Hence, there is a great interest in developing an accurate and robust model to detecting the nitrogen content of rubber tree to improve the production. In this study, we propose a new method for detecting the nitrogen content using fractional calculus augmented NIR spectra. Fractional calculus is applied as a tool to extract additional information from the original spectra. Three different mathematical transforms (R, 1/R, log(R)) are utilized before the fractional order derivative analysis. After derivative analysis with different orders (0–2), the PLS regression method is utilized to develop the estimation models with the wavelengths selected by significant test of correlation coefficient at 0.01 level. The optimal prediction result RP=0.9245 is achieved by reciprocal spectrum with the order 0.6. Results show that fractional calculus with NIR can be utilized to build a more accurate nitrogen estimation model for rubber tree. The result presented here provides us a fast and non-destructive strategy to evaluate the nitrogen condition of rubber tree and provides a direct way to support the field management.

A rheological method exploiting Cole-Cole plot allows gel quantification in Natural Rubber

Raw Natural Rubber (NR) quality, rather variable, is controlled according to international standards (ISO2000, etc.). Despite these standards, better characterization of this complex material is still needed to reduce feedstock waste and energy losses in the manufacturing processes. Twenty-four NR samples were studied. Their gel contents were quantified after dissolution in tetrahydrofuran. The rheological properties of the raw NR samples were measured in double-shear geometry. The Cole-Cole plot of the shear moduli (G″ = f(G′)) was used to graphically calculate an h parameter, described as an indicator of the crosslink density of a polymer. The total gel of NR was found to clearly influence the rheological properties of the material at low frequency. This study also showed that the microgel of NR accounted for 46–92% of the total gel, and cannot be neglected when investigating the influence of gel on NR properties.

Peningkatan mutu blanket karet alam melalui proses predrying dan penyemprotan asap cair

Most of Indonesian rubber products SIR 20 are made from the material of raw rubber obtained from smallholders. However, the quality of this material is not good enough. Thus, quality improvement has to be carried out by manufacturers. The liquid smoke used during the blanket hanging process can improve the quality of the rubber products SIR 20. This research aimed to determine and study the effects of liquid smoke spraying and blanket-hanging duration on the drying factor, the dry rubber content, technical quality, vulcanization characteristics, and physical properties of vulcanized natural rubber. Treatments consisted of various hanging duration (6, 8, and 10 days, and without hanging) and spraying (with and without spraying of liquid smoke). The results showed that the spraying of liquid smoke on natural rubber blankets could improve the technical quality of the natural rubber, especially the values of Po and PRI. The spraying of liquid smoke could reduce the blanket hanging duration to 6-8 days. The blankets sprayed with liquid smoke had the optimum cure time of around 15 minutes and 19 seconds and the scorch time of around 3 minutes and 22 seconds. These values indicated that the vulcanization characteristics of blankets which were sprayed with liquid smoke were generally better than those of blankets which were not sprayed with liquid smoke. Keywords: liquid smoke, natural rubber, blanket quality, hanging.

Sistem Intelijen Peningkatan Mutu Karet di Kabupaten Cilacap

Indonesia is one of the largest rubber exportir in the world. But, the price of rubber from Indonesia is still low because the quality is not within the required standards consumers. Improving quality of rubber is expected to increase farmers' income and region. This study aims to determine the types of strategies involved in improving the quality of rubber in Cilacap regency, Central Java. Analysis using Analytical Hierarchy Process (AHP) and Fuzzy-Multi Expert-Multi Criteria Decision Making (MCDM Fuzzy-ME) obtained the results of selected strategies for improving the quality of rubber in Cilacap District is a technical improvement of rubber cultivation and processing technology improvement. Keywords: Karet, Kualitas, AHP, Fuzzy ME-MCDM

Quality Characterization of Dried Crumb Rubber

Rubber research on how the rubber quality being affected by drying process is rather limited in the public domain. This paper aims to summarize the findings of the quality characterization of rubber based on total rubber network and thermo-oxidative phenomenon based on three different drying strategies (vacuum drying, hot air drying and infrared drying). In this study, vacuum drying has the highest drying rate and internal mass transfer mechanism comparing to hot air drying and infrared drying in a fixed drying condition. The quality test showed that rubber dried at temperature between 65°C to 90°C could ensure preservation of rubber strength as in total rubber network and rubber’s plasticity. There is strong correlation between the drying temperature and rubber quality, where a balance between the drying temperature and the drying time is necessarily to maximize the quality of the dried crumb rubber.

Image Classification of Ribbed Smoked Sheet using Learning Vector Quantization

Natural rubber is an important export commodity in Indonesia, which can be a major contributor to national economic development. One type of rubber used as rubber material exports is Ribbed Smoked Sheet (RSS). The quantity of RSS exports depends on the quality of RSS. RSS rubber quality has been assigned in SNI 06-001-1987 and the International Standards of Quality and Packing for Natural Rubber Grades (The Green Book). The determination of RSS quality is also known as the sorting process. In the rubber factones, the sorting process is still done manually by looking and detecting at the levels of air bubbles on the surface of the rubber sheet by naked eyes so that the result is subjective and not so good. Therefore, a method is required to classify RSS rubber automatically and precisely. We propose some image processing techniques for the pre-processing, zoning method for feature extraction and Learning Vector Quantization (LVQ) method for classifying RSS rubber into two grades, namely RSS1 and RSS3. We used 120 RSS images as training dataset and 60 RSS images as testing dataset. The result shows that our proposed method can give 89% of accuracy and the best perform epoch is in the fifteenth epoch.

Effectiveness of low frequency harvesting systems in rubber smallholder sector of Eastern province (IL2) of Sri Lanka

With no experience on Low Frequency harvesting (LFH) systems in the drier climates, tapping half of the tree circumference once in four days (S/2 d4) instead of traditionally doing once in two days (S/2 d2) was tested in rubber smallholdings established in Eastern Province of Sri Lanka. Yields given by S/2 d4 was slightly higher than that of S/2 d2 and also, found financially more profitable, particularly under hired labour conditions. Quality of raw rubber produced was also not affected by LFH. Seasonal distribution of rubber yields showed that S/2 d4 system outperforms in rainy period whilst yields of S/2 d2 was higher in dry months. Also, demand for labour was higher in the rainy period due to the establishment of seasonal crops. Therefore, it is suggested to apply S/2 d4 only during wet periods (September to March in the following year) and S/2 d2 in dry months (April to August). Reasons for the above responses are also discussed.

Reactive oxygen species in Hevea brasiliensis latex and relevance to Tapping Panel Dryness.

Environmental stress can lead to oxidative stress resulting from an increase in reactive oxygen species (ROS) and involves redox adjustments. Natural rubber is synthesized in laticifers, which is a non-photosynthetic tissue particularly prone to oxidative stress. This paper reviews the current state of knowledge on the ROS production and ROS-scavenging systems in laticifers. These regulations have been the subject of intense research into a physiological syndrome, called Tapping Panel Dryness (TPD), affecting latex production in Hevea brasiliensis. In order to prevent TPD occurrence, monitoring thiol content appeared to be a crucial factor of latex diagnosis. Thiols, ascorbate and γ-tocotrienol are the major antioxidants in latex. They are involved in membrane protection from ROS and likely have an effect on the quality of raw rubber. Some transcription factors might play a role in the redox regulatory network in Hevea, in particular ethylene response factors, which have been the most intensively studied given the role of ethylene on rubber production. Current challenges for rubber research and development with regard to redox systems will involve improving antioxidant capacity using natural genetic variability.

Rubber particle proteins REF1 and SRPP1 interact differently with native lipids extracted from Hevea brasiliensis latex

Rubber particle membranes from the Hevea latex contain predominantly two proteins, REF1 and SRPP1 involved in poly(cis-1,4-isoprene) synthesis or rubber quality. The repartition of both proteins on the small or large rubber particles seems to differ, but their role in the irreversible coagulation of the rubber particle is still unknown. In this study we highlighted the different modes of interactions of both recombinant proteins with different classes of lipids extracted from Hevea brasiliensis latex, and defined as phospholipids (PL), glycolipids (GL) and neutral lipids (NL).We combined two biophysical methods, polarization modulated-infrared reflection adsorption spectroscopy (PM-IRRAS) and ellipsometry to elucidate their interactions with monolayers of each class of lipids. REF1 and SRPP1 interactions with native lipids are clearly different; SRPP1 interacts mostly in surface with PL, GL or NL, without modification of its structure. In contrast REF1 inserts deeply in the lipid monolayers with all lipid classes. With NL, REF1 is even able to switch from α-helice conformation to β-sheet structure, as in its aggregated form (amyloid form). Interaction between REF1 and NL may therefore have a specific role in the irreversible coagulation of rubber particles.

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Smoke liquid is a liquid obtained from smoke condensation during charcoal firing process. The main content of the smoke liquid is acetic acid, hence, can be used as an alternative latex coagulant. Acid in vinegar can reduce the pH of latex and cause the latex to coagulate rapidly. This paper determines effectiveness of using smoke liquid as a latex coagulant and characteristics of the treated latex. The smoke liquid in this study was derived from pine wood. The smoke liquid solutions consisted of the crude smoke liquid and the diluted solution in various concentrations of 5, 10, 15 and 20%. The smoke liquid solution was then each poured into a container of latex. Testing was undergone by observing latex coagulating time, coagulate condition, texture, color, odor and homogenity. The most effective smoke liquid which produced the best latex based on its performances was then taken for further testing of physico-chemical properties which included dry rubber content, plasticity retention index (PRI), initial plasticity (Po), final plasticity (Pa), dirt content, ash content, volatile matter content (Vm), and nitrogen content. Results were then compared with the conventional use of formic acid as a control coagulant. The result showed that the crude and distillate smoke liquid solutions with concentration of 10% produced the best coagulantperformances than the other solutions. Rubber latex treated with the crude smoke liquid produced the best physico-chemical properties and could meet requirements of the Indonesian National Standard (SNI) for Rubber Quality.

In-situ dimensional measurement system for overlapped rubber layers

For the semi-manufactured rubber layers in tire manufacturing industry, the rubber layers need to be joined by the agglutinate conjunction. The width of the conjunction and the rubber thickness must be acquired to ensure the quality of the semi-manufactured rubber. In this investigation, a self-developed dimensional measurement system for agglutinate conjunction is proposed which can be utilized for in situ dimensional measurement during a high-speed manufacturing process. The measured dimensions include both the conjunction width and rubber layer thickness. The standard deviations of the deviations of conjunction widths and the rubber layer thicknesses are about 0.43 and 0.029 mm.

Peningkatan Kinerja Pemasaran Karet Alam Rakyat melalui Optimalisasi Rantai Pasok

Rubber price received by smallholders in Indonesia is lower compared with other countries due to inefficien t marketing system. Therefore, it needs an effort to inc re ase in the supply chain performance. T he objective of the research was to analyze marketing system of natural rubber and the effect of supply chain management on marketing efficiency. The research was conducted at Tebo R egency of Jambi Province from December 2014 until February 2015 . Marketing system was analyzed using B/C ratio and value-added approach, whereas supply chain was carried out using a s upply c hain n etwork approach. The results showed that there were four patterns in the marketing channels of natural rubber. Pattern I (farmers – village traders - subdistrict traders - district traders - industries); Pattern II (farmers – village traders - district traders - industries); Pattern III (farmers –auction market - industries); and Pattern IV [farmers – Rubber Processing and Marketing Unit (RPMU) – industries] . The s upply chain management was only found in the Pattern IV, where there was an agreement between farmers and the RPMU to improve the quality of rubber for higher price. In addition, farmers also received advocation and training from the RPMU . Pattern IV exhibit ed improvement marketing efficiency as indicated by a B/C ratio at 1.29 and value added at 96.82%. The adoption of SCN framework was able to motivate farmers to produce a better quality of rubber that afforded a high er price. Therefore, the government is necessarily to recommend the addoption of t his pattern in increasing farmers’ income.

The Effects on Tensile and Morphology of Ethylene Propylene Diene Monomer Blended with Recycled Nitrile Gloves (EPDM/NBRr)

Blending of two or more polymer together can reduce the cost and better processing advantages of product. Waste rubber powders blending with polymeric materials provide an improvement to the rubber quality. In this work, the effects on tensile and morphology of ethylene propylene diene monomer blended with recycled nitrile gloves (EPDM/NBRr) were studied. Four different compositions of ethylene diene monomer (EPDM) and recycled acrylonitrile butadiene rubber (NBRr) with two different size of NBRr (S1: 250-500μm and S2: 3-10cm) were used. The compositions of EPDM/NBRr prepared were at 95/5, 15/85, 25/75 and 35/65 respectively. The properties of tensile and resilience of EPDM/NBRr blends were determined. Results indicated that the tensile strength and elongation at break (Eb) of EPDM/NBRr blends decrease as increase in NBRr for both S1 and S2. However, the tensile modulus (M100) shows an increment with increase NBRr. Results of resilience decreases and scanning electron microscopy study indicates that when more than 35 phr of NBRr content were used, NBRr exhibited a weak EPDM/NBRr matrix interaction, thus decreasing the mechanical properties of EPDM/NBRr blends. For overall results, 15 phr ratio of NBRr in EPDM/NBRr (S1) blend showed an optimum result respectively.

PERANCANGAN ALAT PENYADAP KARET DI KABUPATEN LANGKAT SUMATERA UTARA DENGAN METODE QUALITY FUNCTION DEPLOYMENT (QFD) DAN MODEL KANO

Rubber plantation is a very important commodity that hold role in Indonesia, especially in Langkat, because about 70% of the main commodities in this district are of agriculture and plantation sector. Aside from being a source of employment for about 1 million people in Langkat, these commodities also make a significant contribution as a source of local revenue from non-oil, sector the raw material suppliers of rubber and play an important role in encouraging the growth of new economic centers in the territories rubber development. To produce a high at quality of rubber, it will need the management and technology of rubber cultivation. This study aims at identifing the factors that influence the design of rubber tapping tool. Tapping is one of the main activities of rubber cultivation to open the latex vessels in the bark so that the latex is flowing fast. The speed of latex flow will be reduced when the dose of latex liquid in the skin is reduced. To obtain a good result of tapping, tapping must follow certain rules in order to obtain high production, profitable, and sustainable while maintaining plant health factors. The results showed that the type of micro-enterprises dominate total type of business in the city of Medan about 33,5% by the age of the business more than 10 years. In the design of the rubber tapping tool, the main issues are the level of iron and wood strength. Both of these problems cause the rubber tapper tool easily damaged, so when use the tool, the skin of rubber tree is damaged.

Quality improvement of pyrolysis oil from waste rubber by adding sawdust

This work was aimed at improving the pyrolysis oil quality of waste rubber by adding larch sawdust. Using a 1kg/h stainless pyrolysis reactor, the contents of sawdust in rubber were gradually increased from 0%, 50%, 100% and 200% (wt%) during the pyrolysis process. Using a thermo-gravimetric (TG) analyzer coupled with Fourier transform infrared (FTIR) analysis of evolving products (TG–FTIR), the weight loss characteristics of the heat under different mixtures of sawdust/rubber were observed. Using the pyrolysis–gas chromatography (GC)–mass spectrometry (Py–GC/MS), the vapors from the pyrolysis processes were collected and the compositions of the vapors were examined. During the pyrolysis process, the recovery of the pyrolysis gas and its composition were measured in-situ at a reaction temperature of 450°C and a retaining time of 1.2s. The results indicated that the efficiency of pyrolysis was increased and the residual carbon was reduced as the percentage of sawdust increased. The adding of sawdust significantly improved the pyrolysis oil quality by reducing the polycyclic aromatic hydrocarbons (PAHs) and nitrogen and sulfur compounds contents, resulting in an improvement in the combustion efficiency of the pyrolysis oil.

Influence of Ground Tyre Rubber Devulcanisates on Morphology and Properties of Tread Tyre Formulation

The use of reclaimed and devulcanised material in virgin rubber compounds has attracted the attention of many rubber industries due to increasing raw material costs, diminishing resources and growing awareness of environmental issues. Several methods have been developed to reclaim rubber waste, for example, thermo-and chemo-mechanical processes, microwave regeneration, microbial action and ultrasonic regeneration. However, extensive research on processes for high-quality recycling materials based on waste tyres is still lacking. In this study, optimised processing conditions for the devulcanisation of whole passenger car tyres using diphenyldisulphide (DPDS) as a devulcanisation aid will be applied. The devulcanised ground tyre rubber (D-GTR) obtained from the process was blended on top of the original tyre tread formulation at different concentrations. The results so far indicate that the addition of D-GTR influences the properties of the blend, but to a lesser extent than the commercially used powder or reclaim types do, for which loadings less than 5% can be applied. The main reason for the influence of D-GTR on the rubber properties is inhomogeneities in the D-GTR/virgin rubber blend and quality aspects of raw GTR.

Genetic parameters in a rubber tree population: heritabilities, genotype-by-environment interactions and multi-trait correlations

Rubber tree breeding programs are mainly driven by selection of individuals with high yield and quality of rubber. Data from 51 open-pollinated progenies tested on six sites in Brazil were analyzed over several traits to estimate the following: genetic parameters such as narrow-sense heritability and additive genetic variance in single- and multi-site analyses, type B correlations to determine the relevance of genotype-by-environment interactions and its effects on alternative selection strategies, additive genetic repeatability correlation for rubber yield based on three consecutive yearly measurements, and type A correlations to evaluate trait-to-trait genetic associations for all measured traits. Average rubber yield (RYm) showed an estimated narrow-sense heritability of 0.31, with an estimated type B correlation of 0.84, indicating low levels of genotype-by-environment interaction. The trait survival and number of latex vessel rings (RG) showed larger genotype-by-environment interaction and the lowest heritabilites. High to moderate type B correlation was found for most traits, with a value of 0.85 between diameter (or girth) and RYm; therefore, it is possible to achieve interesting rubber yield genetic gains (over 3 years of measurements) from indirect selection based on diameter at age 2.

Effect of Surface Grinding Process Parameters on Surface Quality of Natural Rubber (NR) Liner’s of pipe line

Effect of Surface Grinding Process Parameters on Surface Quality of Natural Rubber (NR) Liner’s of pipe line