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INFLUENCE OF COAGULANTS TO THE PRODUCTION OF CUP LUMP AND STANDARD THAI RUBBER (STR20) ON THE PROPERTIES OF RUBBER
No full textThe STR rubber from the production factory in the northeastern provinces of Thailand. It is due to the fact that some of the suppliers of rubber coagulants add sulfuric acid in the cup lump process, resulting in high levels of sulfate residues in rubber, which is becoming a new problem affecting the rubber industry in these provinces. Moreover, the acid has an impact on the properties of rubber , the health of workers in the rubber plantation and place to purchase, including the problem of bad-smelling serum water down the road and causing trouble to the road users and the community. If the problem happens, the damage in the country is observed. The cup lump coagulants of 16 samples, selected by a random sampling, from the northeastern provinces of Thailand were analyzed by the ion chromatography method. The results demonstrate that the cup lump coagulants of 8 samples containing sulfuric acid and of 5 samples containing calcium chloride were detected, accounting for 50% and 31.25 % of total samples, respectively. Rubber cup lumpcontains sulfuric acid and calcium chloride. It results in the rubber latex such as viscous gum, dark color, high viscosity, resistance to low deterioration and high moisture. The 5 samples of coagulants were selected to represent all of the rubber coagulants, i.e. 1) coagulants with single formic acid, 2) coagulants with single sulfuric acid, 3) coagulants with single calcium chloride, 4) coagulants mixing between sulfuric acid and calcium chloride, and 5) coagulants mixing between formic acid and calcium chloride. The cup lump was prepared by practical method in the rubber plantation. It was prepared to dry rubber, grinding and drying in order to analysis the properties of rubber such as raw rubber, rubber compound and rubber after vulcanization. The results from analyzing the properties of rubber prove that the coagulant with formic acid is consistent with the STR20 standard. The properties of raw rubber, coagulated by coagulants containing between sulfuric acid and calcium chloride tend to have the value of volatile or volatile matter and ash content, exceeding the standard. In addition, Original Wallace Plasticity (PO) is lower than the STR20 standard. From analyzing the rubber compound, coagulated by coagulants containing formic acid, the mechanical properties of rubber such as tensile strength , modulus of 100%, 300% and 500%, respectively, were obtained. It is higher than coagulated by coagulants containing between sulfuric acid and calcium chloride
EFFECT OF FERTILIZATION AND STIMULATION OF HEVEA BRASILIENSIS TREES ON MINERAL COMPOSITIONS AND PROPERTIES OF PRODUCED LATEX AND RUBBER
No full textThis publication reports the mineral composition and the properties of latex and rubber obtained from a fertilizer agronomical trial conducted in Kasetsart University Sitthiporn Kritsadakon Research Station, south Thailand. This trial was designed to study the effect of 4 fertilizer levels on RRIM600 clone trees tapped with the recommended tapping system (S/2 d2) with or without stimulation (ET2.5% 4/y). Latex and rubber characterization was conducted on biannual sampling campaigns from 2014 to 2017. Nitrogen (N) and mineral (P, K, Mg, Ca, Ashes) contents were measured on latex and USS rubber made from this latex. Dry Rubber Content (DRC) and Mechanical Stability (MST) of latex as well as Wallace plasticity (P0), plasticity retention index (PRI) of USS rubber were measured. After 3 agronomical years, latex yield was found to be increased by both fertilization level and stimulation. Concerning N and mineral compositions of latex and USS rubber, no significant effect of fertilization was observed. However, stimulation application was found to be associated with the increase of P content of latex and N, P and Mg contents of USS rubber. Concerning the physical properties of latex (DRC, MST) and USS rubber (P0, PRI), none of these indicators was found to be influenced by either fertilization levels, or stimulant application or their interaction Finally, comparison between latex and USS rubber mineral contents showed that most of P (60%), Mg (82%), and K (89%) was leached in the waste water during the USS making process while the majority of N (34% leached) and the totality of Ca stayed within rubber. The mineral content of the USS process waste water was found to be in the same order of magnitude as the amount brought by fertilizer. Hence, USS process water recycling could be an option to consider.Keywords: natural rubber, fertilization, mineral export in latex, mineral loss, rubber sheet process, rubber qualit
EKOPRENATM AS A REINFORCEMENT MODIFIER FOR GRAPHENE OXIDE/CARBON BLACK FILLED NATURAL RUBBER
No full textGraphene oxide (GO) has emerged as a new layered carbon nanomaterial due to its outstanding strength. However, to disperse GO sheets into a nonpolar rubber matrix such as natural rubber is a challenge. In this study, EkoprenaTM or epoxidised natural rubber (ENR) was used as a reinforcement modifier for hybrid filler graphene oxide/carbon black (GO/CB) filled natural rubber (NR). Three grades of ENR containing different levels of epoxide functional group (eg. 50%, 60% and 75%) were used to investigate the effect of polar functionality on the reinforcing efficiency of graphene oxide in natural rubber. The study has shown that the incorporation of ENR was found to reduce filler-filler interaction and to improve technological properties. The epoxide functionality on natural rubber opens the possibility of interaction with graphene oxide as indicated by the significant changes in the Tg.  The  best  levels of  reinforcement were  found with  the  addition  of  ENR-60 as reinforcement modifier.Keywords:  EkoprenaTM; epoxidised natural rubber; graphene oxide; natural rubber nanocomposite; reinforcement modifier
LEAF NUTRIENT STATUS OF RUBBER TREE IN DIFFERRENT ECOLOGY ZONE OF NORTH SUMATRA
No full textA study of nutrient status of rubber leaf in five years after planting in terms of the difference of growth location was conducted in three rubber ecology zones of North Sumatra i.e. AL, LI and TE. During the immature period, all zones were applied 500 g of N, 200 g P2O5, 350 g K2O and 50 g MgO. The result showed that general recommendation of fertilizer was just able to make sufficient of nitrogen in AL and TE zones (0.6% and 0.46% respectively); available phosphorus in AL zone (23.57 ppm); exchangeable potassium in Al zone (0.49 me 100g-1); exchangeable magnesium in AL and TE consecutive 1.76 and 2.08 me 100 g-1. Nitrogen, phosphorus, potassium and magnesium in the soil of AL, LI and TE zones relatively had a positive correlation with leaf nutrient status. N and Mg showed stronger positive correlation than P and K with coefficient of correlation 0.55 and 0.64 respectively. An indepth comprehensive study in relation to fertilizer dosage of immature rubber period (TBM) regarding soil and leaf analysis is important to be conducted.      Keywords: Hevea brasiliensis, nutrient, leaf, soi
PERFORMANCE OF ONCE IN THREE DAYS (S/2 d3) AND FOUR DAYS (S/2 d4) TAPPING SYSTEMS IN MARGINAL DRIER AREAS IN SRI LANKA
No full textWith the beginning of tapping in the first ever rubber lands planted in drier climates, low frequency tapping (LFT) systems i.e. tapping half of the tree circumference once in three (S/2 d3) and four (S/2 d4) days were tested together with traditional once in two days (S/2 d2) system in rubber smallholdings established in marginal drier areas in Eastern Province of Sri Lanka. Generally, yields given by LFT systems were comparatively higher than that in traditional S/2 d2 system. A prominent seasonal distribution of rubber yields was shown in all three taping systems. Throughout the period dry rubber content of latex did not fall below 35%. When compared to wet areas sucrose, inorganic phosphorous, thiol and total solid content of latex were considerably higher with a prominent variation between wet and dry seasons. When reducing the tapping frequency latex sucrose content reduced whilst latex inorganic phosphorous content increased confirming the higher metabolic activity in laticifers to increase daily latex yield per tree. Lowering of the plugging index in trees taped with LFT systems, significantly increase the daily latex volume. Low frequency tapping systems did not effect on the growth of rubber tree, incidence of tapping panel dryness and quality of rubber produced. Converting to LFT increased the profitability and time availability of farmers for their traditional farming activities. Keywords : Cost of production, Hevea, low frequency tapping, rubber, tappin
POLICY OPTIONS FOR MANAGING FARM INCOME UNDER MARKET UNCERTAINTIES
No full textThe past few years have shown that the world supply sector of natural rubber (NR) could exert little influence on the market price. Since the NR market is largely driven by non-fundamental factors, efforts by governments and international bodies in stabilizing the market yield insignificant results. To sustain the world supply of NR, it is necessary to safe-guard rubber farmers’ income based on rubber cultivation activities. There are options to increase rubber growers’ income despite the ruled market price. To farmers, the improvement of latex yield, the reduction of cost, the generation of additional income from the field, and the enhancement of product quality are suggested. Governments may have measures to redesign the supply chain, provide economically viable supports to the supply chain, regulate the growth of the production, and raise the awareness of farmers of good saving practices. These options can be achieved by formulation and implementation of suitable long-term holistic polices to safe-guard farmers’ net return from rubber cultivation
Front Matter
No full textFront Matter of the Proceedings of the IRC 2017 consits of Preface, Contents, Opening Address, and Closing Addres
DISAIN DAN PENGUJIAN SISTEM KENDALI SUHU ASAP KAYU KARET UNTUK MENINGKATKAN EFEKTIVITAS PEMBUATAN KARET SIT ASAP BERBASIS MIKROKONTROLLER
Get PDFPengasapan karet RSS adalah metode pengawetan dan pengeringan karet lembaranmenggunakan asap kayu bakar agar jamur tidak tumbuh saat penyimpanan. Pada umumnya pengasapan karet RSS konvensional membutuhkan waktu 5-6 hari dan konsumsi kayu asap sebanyak 4 m3 per ton karet kering. Selain itu mutu RSS juga ditentukan oleh pengontrolan yang rutin mengenai bahan bakar kayu dan suhu ruang pengasapan. Penelitian ini berupaya meningkatkan mutu karet RSS dan efisiensi energi proses pengasapan karet RSS dengan menerapkan sistem kendali otomatis berbasis mikrokontroller yang dapat mengatur konsentrasi asap dan suhu. Sistem kendali ini merupakan sistem yang akan mengatur suhu dan kepekatan asap pada setiap tingkatan suhu. Tujuan penelitian ini adalah untuk melakukan perancangan dan pengujian pengendalian suhu dan konsentrasi ruang asap karet RSS menggunakan mikrokontroller. Prosedur penelitian ini mencakup; 1) Disain dan Konstruksi, 2) Merancang perangkat keras kendali, 3) Merancang perangkat lunak, 4) Kalibrasi Sensor LM 35 dan 5) Pengujian sistem kendali pada ruang pengasap. Hasil pengujian sistem kendali suhu dan konsentrasi asap adalah proses pengasapan karet RSS terbagi pada 4 tingkatan suhu yaitu suhu 400C-450C selama 12 jam, suhu 450C-500C selama 12 jam, suhu 500C-550C selama 12 jam, dan suhu 550C-600C selama 24 jam. Keberhasilan pengujian ini dicapai selama 60 jam atau 2,5 hari. Mutu karet RSS berwarna coklat transparan, tidak timbul gelembung dan lembaran tidak tambah panjang atau putus. Karet RSS menjadi dominan mutu RSS 1 setelah terjadi penguapan air sebesar 35,78%. Adapun panjang karet RSS berkurang sebesar 3,81%, lebar berkurang sebesar 8,95% dan ketebalan bertambah sebesar 4,36%. Penggunaan kayu bahan bakar asap sekitar 2 m3 dengan kapasitas karet RSS 1.000 Kg
PENGARUH STIMULAN ETEFON TERHADAP PRODUKSI DAN FISIOLOGI LATEKS BERBAGAI KLON IRR
Get PDFStimulan telah umum digunakan pada perusahaan perkebunan untuk mengoptimalkan tenaga kerja dan produksi. Aplikasi stimulan dapat meningkatkan lama aliran lateks dan metabolisme sel lateks. Namun aplikasi stimulan etefon seringkali tidak sesuai dengan kemampuan tanaman. Penerapan etefon stimulan dalam sistem eksploitasi hendaknya sesuai dengan tipologi klon. Tujuan penelitian ini adalah untuk mengetahui frekuensi stimulan yang optimal pada masing-masing klon dengan memperhatikan kondisi fisiologis dan kesehatan tanaman. Penelitian dilaksanakan di Kebun Percobaan Balai Penelitian Sembawa mulai 2011 hingga 2014, menggunakan klon IRR 24, IRR 41, IRR 100, IRR 105, dan IRR 118, tahun tanam 2002. Penyadapan mulai dilakukan pada panel B0-1 dengan sistem sadap S/2 d3 ET2.5%. Frekuensi stimulan diaplikasikan berbeda-beda pada setiap klon sesuai dengan hasil analisis lateks sebelum perlakuan. Hasil penelitian menunjukkan frekuensi stimulan yang optimum untuk tiap klon berbeda-beda. Produksi optimal pada IRR 24 dan IRR 100 dicapai pada kondisi tanpa stimulan, stimulan justru meningkatkan risiko kering alur sadap (KAS). IRR 41, IRR 105, dan IRR 118 respon terhadap stimulan. Kondisi tersebut didukung dengan kapasitas metabolisme dan kadar sukrosa lateks sebelum stimulan. Faktor pembatas peningkatan produksi adalah kadar sukrosa tanpa stimulan dan kemampuan tanaman dalam mengaktifkan metabolisme
