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Kinetic studies on thermal degradation of natural rubber/butyl rubber Muhammad Sholeh; ihda Novia Indrajati; Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 34, No 1 (2018): Majalah Kulit, Karet dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

The knowledge of how rubber breakdown on heating in oxidative environment is important in processing and using the material. In the present work, we performed thermogravimetric analysis and utilized three iso-conversional kinetic models to get apparent activation energies of thermal degradation of natural rubber/butyl rubber. Blending of RSS/butyl and additives was done using a laboratory two-roll mill. Cure time of the blended compound was determined by a moving die rheometer. The compound was compression moulded at 160°C with a pressure of 150 kg/cm2 using a laboratory hot press. Thermogravimetric analysis was carried out from 30°C to 800°C in air flow of 200 ml/min with heating rates of 5, 10, 15, and 20°C/min. The kinetic parameters were determined by three isoconversional models (Kissinger, Doyle, and Flynn–Wall–Ozawa model). The result revealed that the thermal decomposition of the blend occurs in two stages, DTG peaks tends to shift to a higher temperature and the values of DTG peaks increase with the increase of heating rate, and the three isoconversional models gave similar apparent activation energies. The activation energy obtained can be used to predict thermal lifetime of the material.

Quality of rubber hospital sheeting Herminiwati Herminiwati; Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 6, No 10-11 (1991): Majalah Barang Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

13 (thirteen) samples of Rubber hospital shetting of various trademark which were taken from manufacturers and markets in Bandung, Yogyakarta and Surabaya, had been tested for the purpose of this research. Quality of rubber hospital sheeting is determined by factors that onsure either the strength or wearm by testing them in accorfance with test method as described in ASTM.It could be found from the test results that : the thickness was 0,406 0,506 mm, breaking strength 54,47 – 77,85 kg/cm2. Elongation ata break 99,8% -147,8%.The rubber hospital sheeting was also subjected to hyfrostatic water resistance test and no leakange was accured.It had good steam strikization, accelerated Aging, phenol and alcohol resistance aw well. INTISARI Dalam penelitian ini telah diuji 13 sample perlak karet untuk rumah sakit dari berbagai merk yang diambil langsung dari pabrik maupun pasaran di darah Bandung, DI Yogyakarta dan Surabaya.Mutu perlak karet untuk rumah sakit ditentukan berdasarkan pada factor-faktor yang menajmin menutut ASTM. Dari hasil pengujian diperoleh hasil sebagai berikut tebal 0.406 – 0.506 mm, tegangan putus 54.48 77.85 Kg/cm2, pepanjang putus 99.8 – 147,8 %. Pelak karet yang diuji tidak tembus air dalam pengujian hydrostatic water resistance, juga mempunyai ketahanan terhadap sterilisasi uap, ketahanan terhadap penguasangan, ketahanan terhadap ketahanan terhadap alkokol yang baik.

Penggunaan precipitated calcium carbonate (PCC) sebagai filler untuk sol karet sepatu olah raga Herminiwati Herminiwati; Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 26, No 1 (2010): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20543/mkkp.v26i1.240

The objective of the research was to investigate the utilization of Precipitated Calcium Carbonate (PCC) as filler in producing sport shoe rubber soles. PCC is a white filler needed for production of nonblack colour rubber products. There are four types of PCC that have been used including two local PCC from Wonosari and East Java, and two imported PCC from Japan and Taiwan. The amount of PCC added into the sport shoe sole rubber compound was varied in 30,45,60,75 and 90 per hundred rubber (phr). The compounding was carried-out by using two roll mills machine, and the compound was subsequently measured their optimum vulcanization time by using rheometer. The produced compound was then subjected to vulcanistion process by using hydrolic press at temperature 1500C and pressure 150 kg/ cm2. The quality of shoes sole vulcanisates were compare to standard quality of SNI. 12-7075-2005 about cemented system sport shoes. The results indicated that the best formula of rubber compound for sport shoes sole were made by using NR 80 phr, NBR 20 phr, paraffinic oil 10 phr, aluminium silicate 30 phr, ZnO 5 phr, TiO2 10 phr, stearic acid 1 phr, vulkanox SP 1 phr, paraffin wax 1 phr, TMTD 0,5 phr, CBS 2 phr, sulphur 1,2 phr with the amount of PCC Actifort 700 of 45 phr. The best formula meet the requirement SNI 12-7075-2005 and they were characterized by tensile sterength 16,79 N/mm2, elongation at break 529,92% tear resistance 9,06 N/mm2, specific gravity 1,28 g/cm3, hardness 55 shore A, Grasselli absrassion resistancing filler. The local PCC from Wonosari can be used for substitution of the imported PCC as the white filler for the production of rubber compound sport shoes sole. However, particle size reduction and coating or surface treatment of local PCC were needed for improving the quality and the role of reinforcing filler. Keywords : PCC, filler, sole, sport shoes. Tujuan penelitian adalah untuk mengetahui pengaruh penggunaan Precipitated Calcium Carbonate (PCC) sebagai filler dalam pembuatan sol karet sepatu olah raga. PCC merupakan filler putih yang diperlukan dalam pembuatan barang-barang karet yang tidak berwarna hitam. Empat jenis PCC yang terdiri atas dua jenis PCC local dari Wonosari dan Jawa Timur dan dua jenis PCC impor dari Jepang dan Taiwan digunakan sebagai filler untuk pembuatan sol karet sepatu olahraga. Jumlah PCC yang ditambahkan dalam kompon karet sol sepatu olah raga divariasi berturut-turut 30,45,60,75 dan 90 phr (per hundred rubber). Proses pembuatan kompon dilakukand engan mesin two roll mill dan kompon yang diperoleh diukur waktu vulkanisasi optimumnya dengan rheometer. Kompon selanjutnya divulkanisasi dengan mesin kema hidrolik pada suhu 1500C dan tekanan 150 kg/ cm2. Kualitas vulkanisat sol sepatu diujji menurut ketentuan dalam SNI. 12-7075-2005 tentang sepatu olah raga dengan system lem. Hasil penelitian menunjukkan bahwa formula kompon karet sol sepatu olah raga terbaik terdiri atas karet alam 80 phr, NBR 20 phr, paraffinic oil 10 phr, aluminium silikat 30 phr, ZnO 5 phr, TiO2 10 phr, asam stearate 1 phr, vulkanox SP 1 phr, parafin wax 1 phr, TMTD 0,5 phr, CBS 2 phr, sulfur 1,2 phr dengan jumlah PCC Actifort 700 yang ditambahkan sebesar 45 phr. Formula terbaik memenuhi persyaratan SNI dan ditandai oleh sifat fisik sebagai berikut : tegangan putus 16,79 N/mm2, perpanjangan putus 529,92 %, ketahanan sobek 9,06 N/mm2, bobot jenis 1,28 cm3, kekerasan 55 shore A, ketahanan kikis Grasselli 1,0 mm3/kg m, ketahanan retak lentur baik dan tidak retak. Ini menunjukkan bahwa PCC Actifort 700 merupakan filler penguat. PCC local asal Wonosari dapat digunakan untuk mensubstitusi PCC impor sebagai filler putih dalam pembuatan karet sol sepatu olah raga. Akan tetapi PCC local memerlukan pengecilan ukuran partikel dan perlakuan permukaan atau coating untuk meningkatkan kualitas dan peranannya sebagai filler penguat. Kata Kunci : PCC, filler, sol, sepatu olahraga.

Kualitas udara disektor industri karung plastik Arum Yuniari; M. Sri Wahyuni; C. Yuwono Sumasto
Majalah Kulit, Karet, dan Plastik Vol 12, No 25 (1998): Majalah Barang Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

Air pollution is generated by air pollutant in production. Raw materials used in the production of plastic corrugated sack are Polyethylene and Polypropylene. Polyethylene and Polypropylene yars are knitted to be various plastic knits such as plastic corrugated sacks. The result of this study shows that concentration of dust particles in processing area is 30 – 34 ugr/m3, and in finishing area is 38,6- 972 ugr/m3. The other gases such as Ox, SO2, H2S and NH3 are still low. The overage concentration of dust particle in ambient air is about 38,6 – 380 ugr/m3. However for parameter of Ox, SO2, H2S and NH3 seems stile low. INTISARI Karung plastik merupakan salah satu bentuk pengemas yang sangat penting pada sektor industri. Peningkatan jumlah industri karung plastik memberikan dampak terhadap lingkungan sekitar. Terjadinya pencemaran udara dapat diakibatkan oleh gas buang yang dikeluarkan pada proses produksi. Bahan baku yang dipakai dalam pembuatan karung plastic adalah Polietilen dan Polipropilen. Benang-benang plastic ditenun menjadi aneka tenun plastik, misalnya karung plastik. Hasil penelitian terhadap gas buang pada ruang proses produksi dan ruang finishing masih dibawah nilai ambang batas Hygyene Perusahaan dan Kesehatan Kerja. Konsentrasi udara dilingkungan sekitar yang melebihi ambang batas adalah parameter debu 0,344 – 0,380 mgr / m3. Untuk parameter Ox, SO2, H2, dan NH3 sudah memenuhi baku mutu Kep. 02/MENKLH/I/1988.

Penelitian pembuatan kompon tegel karet dengan menggunakan paraffinic oil pertamina sebagai plasticizer Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 9, No 18 (1994): Majalah Barang Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

The objective of the research is to find out the maximum quantity of paraffinic oil as plasticizer which can be added to rubber tile compound which fulfills the requirement of SNI 1550-89-A, “Tegel Karet”. The compound is made by applying RSS, SBR 1502, Paraffinic oil, Stearic Acid, ZnO, PBN, Aluminium Silicate, Chine Clay, CaCO3, pigment, MBT and sulfur, then compounded by two roll mill machine. Compound is moulded into slab forms using hydraulic press machine based on the time and temperature obtained from the curometer divice, pressure 150 kg/cm2. The slab is tested its physical properties including hardness, compression set and also observed organoleptically. Test result which fulfill the requerement of SNI 1550-89-A : “Tegel Karet” are a compound applying Paraffinic 90 type 2 and 3, 7,5 Parts. ABSTRAKPenelitian ini bertujuan untuk mengetahui jumlah maksimum Paraffinic oil yang dapat ditambahkan dalam pembuatan kompon Tegel Karet yang memenuhi persyaratan SNI 1550-89-A “Tegel Karet”. Pembuatan kompon menggunakan RSS, SBR 1502. Paraffinic oil, asam stearat, ZnO, PBN, Aluminium Silikat, China Clay, CaCO3, Zat Warna , MBT, sulfur, Aluminium Silikat, China Clay, dikomponding, dengan menggunakan mesin two roll mill. Kompon cetak, tekanan 150 kg/cm2. Kompon diuji kekerasan dan pampatan tetap dan diamati secara organoleptis. Dari hasil penelitian kompon tegel karet yang menggunakan Paraffinic oil tipe 2 dan 3 dengan jumlah 7,5 bagian dapat memenuhi persyaratan SNI 1550-89-A, “Tegel Karet”.

Sifat mekanik dan morfologi termoplastik elastomer (TPE) hasil polipaduan NBR/PVC dan maleat anhidrat Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 28, No 1 (2012): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20543/mkkp.v28i1.201

ABSTRACTThe research of thermoplastic elastomer NBR/ PVC and maleic anhydride (MAH) aimsto determine the effect of maleic anhydride (MAH) as compatiblizer on the mechanicalproperties and morphology of thermoplastic elastomer NBR / PVC. Mixing between the NBRand PVC performed using a two roll mill with a temperature range of 60-80 º C, the vulcanizationprocess using a hydraulic press at a temperature of 170 º C, pressure of 150 kg/cm2. Compositionof the NBR / PVC successively varied: 90/10: 85/15 /: 80/20: 75/25: 70/30 and 65/35, being theamount of maleic anhydride (MAH) as compatibilizer used are 4 and 5 phr. Mechanicalproperties were evaluated including tensile strength, elongation at break, hardness andcompression set according to ASTM procedure.Thermal treatments were performed by means ofthermogravimetry (TG) and morphology of the blend by scanning electron mycroscopy (SEM).Test results showed that MAH compatibilizer be able to improve the mechanical properties oftensile strength and elongation, and compresion set. Morphological observation by SEM showedthat the addition of MAH causes more homogeneous mixture. Thermal analysis by TG appearsthat the melting temperature of the mixture was 252 º C.Keywords: thermoplastic elastomer, NBR, PVC, maleat anhydride.ABSTRAKPenelitian termoplastik elastomer polipaduan NBR/PVC dan maleat anhidrat (MAH)bertujuan mengetahui pengaruh kompatibliser maleat anhidrat (MAH) terhadap sifat mekanikdan morfologi termoplastik elastomer NBR/PVC. Pencampuran antara NBR dan PVC dilakukanmenggunakan two roll mill dengan rentang suhu 60 80 ºC, proses vulkanisasi menggunakanhydraulic press pada suhu 170 ºC, tekanan 150 kg/cm2. Komposisi NBR/PVC divariasi berturutturut:90/10; 85/15/; 80/20; 75/25; 70/30 dan 65/35. Jumlah kompatibiliser maleat anhidrat(MAH) yang digunakan adalah 4 dan 5 phr. Pengujian sifat mekanik meliputi tegangan putusdan perpanjangan putus, kekerasan dan compression set menggunakan metode ASTM.Morfologi termoplastik vulkanisat diuji menggunakan SEM dan DTA. Hasil pengujianmenunjukkan bahwa kompatibiliser MAH mampu meningkatkan sifat mekanik tegangan putusdan elongation dan compresion set. Pengamatan morfologi dengan SEM menunjukkan bahwapenambahan MAH menyebabkan campuran lebih homogen. Analisis termal dengan TG tampakbahwa suhu leleh campuran adalah 252 ºC.Kata kunci: termoplastik elastomer, NBR, PVC, maleat anhidrat.

Pengaruh penerapan teknologi vakum dan non-vakum terhadap umur simpan pangan berminyak Isananto Winursito; Arum Yuniari
Majalah Kulit, Karet, dan Plastik Vol 21, No 1 (2005): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20543/mkkp.v21i1.315

Research about the application of vaccum and non vacuum technology for the storage of greasy food using two types of polyethylene (0. Mm) and bilayer (polyethylene and nylon 0.09 mm) was carried out. The objective of the research was to know the influence of packaging for technology storage of greasy foods (sambel pecel). The result showed that water vapour permeability of bilayer was lower than of polyethylene and the score was 1.72 mg/24 hours for polyethylene and 1.58 mg/24 hours bilayer. Water activity (aw) after 60 days storage was 0.43-0.56. while the score of peroxide value of greasy foods packed using non vacuum technology was 10.18-24.98 mg Fe2+ and the score of greasy foods (sambel pecel) using vacuum technology was 10.18-17.48 mg Fe2+ and the score of greasy foods (sambel pecel) using vacuum technology was 10.18-17.48 mg Fe2. Sensories evaluation of greasy foods indicated with bilayer and vacuum technology gave high score. Key words: greasy food, vacuum, non vacuum, polyethylene, bilayer plastic. ABSTRAKPenelitian mengenai penerapan teknologi vakum dan non vakum terhadap umur simpan pangan berminyak (sambel pecel) menggunakan bahan polietilen (0,1 mm) dan bilayer (0,09 mm). tujuan penelitian ini untuk mengetahui pengaruh teknologi pengemasan terhadap umur simpan pangan berminyak (sambel pecel). Hasil penelitian menunjukkan bahwa permeabilitas terhadap uap air bilayer lebih rendah dari polietilen dan nilainya adalah polietilen 1,72 mg/24 jam dan bilayer 1,58 mg/24 jam. Aktivitas air setelah disimpan 60 hari adalah 0,43-0,56. Nilai peroksida dari sambel pecel yang dikemas non vakum adalah 10,18-24,98 mg Fe2 dan untuk vakum 10,18-17,48 mg Fe2. Hasil evaluasi uji sensoris menunjukkan bahwa sambel pecel yang dikemas dengan bilayer dan vakum teknologi memperoleh nilai tinggi.Kata kunci: sambel pecel, vakum, non vakum, polietilen, plastic dua lapis.

Pengaruh sulfur terhadap sifat fisika campuran pale crepe dan SBR untuk karet tahan panas Arum Yuniari; Nursamsi Sarengat; Sri Brataningsih Puji Lestari
Majalah Kulit, Karet, dan Plastik Vol 29, No 2 (2013): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20543/mkkp.v29i2.181

ABSTRACTSulfur plays an important role in the rubber vulcanization process especially in the formation of crosslinks. Heat resistant rubber made from mixing pale crepe and SBR requires the right amount of sulfur as crosslinking agent. The purpose of the study was to determine the effect of the addition of sulfur on the changes in physical properties before and after aging. Heat resistant rubber was made with variation of pale crepe/SBR: 80/20; 70/30; 60/40; 50/50 phr and sulfur variation of 1; 1.5 phr. The results showed that sulfur was influential in the crosslinks formation. The addition of 1 phr sulfur gave higher physical properties of the vulcanized with 1.5 phr sulfur. The changes of physical properties after aging process of the vulcanized with sulfur 1 phr was lower than the vulcanized with sulfur 1.5 phr. Vulcanized pale crepe/SBR (70/30) with 1 phr sulfur could be applied as heat-resistant rubber products. Keywords: Pale crepe/SBR blends, sulfur, physical properties, heat resistant rubber ABSTRAKSulfur memegang peranan penting dalam proses vulkanisasi karet terutama dalam hal pembentukan ikatan silang. Karet tahan panas yang dibuat dari pencampuran pale crepe dan SBR membutuhkan sulfur dalam jumlah yang tepat sebagai crosslinking agent. Tujuan dari penelitian adalah untuk mengetahui pengaruh penambahan sulfur terhadap perubahan sifat fisika sebelum dan sesudah aging. Karet tahan panas dibuat dengan variasi pale crepe/SBR: 80/20; 70/30; 60/40; 50/50 phr dan variasi sulfur 1 dan 1,5 phr. Hasil penelitian menunjukkan bahwa sulfur sangat berpengaruh terhadap pembentukan ikatan silang. Penambahan sulfur 1 phr memberikan sifat fisika lebih tinggi dari pada vulkanisat dengan sulfur 1,5 phr. Perubahan sifat fisika sesudah aging untuk vulkanisat dengan sulfur 1 phr lebih kecil dari vulkanisat dengan sulfur 1,5 phr. Vulkanisat pale crepe/SBR (70/30) dengan sulfur 1 phr dapat digunakan untuk produk karet tahan panas. Kata kunci: Pale crepe/SBR blends, sulfur, sifat fisika, karet tahan panas.

Komposit dari sampah plastik fleksibel dan serbuk gergaji Dwi Wahini Nurhajati; Arum Yuniari; Herminiwati Herminiwati; Sri Brataningsih Puji Lestari
Majalah Kulit, Karet, dan Plastik Vol 19, No 1 (2003): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

A composite made from the flexsible plastic waste and saw dust was studied. The objectives of this research was to find the optimum ratio of the flexible plastic waste and saw dust in its application on a floor tile. The investigated ratio of flexible plastic waste / saw dust were 100/0; 90/10; 80/20; 70/30; 60/40; and 50/50 respectively. The composites were prepared on a rheocord-90 machine at 600C for 10 minutes. The composites were tested for their physical properties I, e flexibility, dimensional stability, curling, volatility, tensile strength, elongation at break, and hardness. The physical properties testing result show that a composite by using the flexible plastic waste and saw dust in comparation of 90/10 could meet the requirements of SNI 03/4060/1996 for Vinyl Floor. The increasing saw dust content in composites decreased tensile strength, elongation at break, flexibility, and hardness, but increased dimensional stability, and volatility. Tensile strength of all composites was higher than particle board. Keywords : composites, flexible plastic waste, saw dust, floor tile.

Sifat fisika dan analisis gugus fungsi karet seal o-ring dari bahan termoplastik elastomer nitrile butadiene rubber (NBR) dan polyvinyl chloride (PVC) Arum Yuniari; Nursamsi Sarengat
Majalah Kulit, Karet, dan Plastik Vol 29, No 1 (2013): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

ABSTRACTThe purpose of this research was to determine the physical properties and functionalgroups on O-ring rubber seals made of thermoplastic elastomers blend NBR and PVC.Composition of the NBR / PVC were successively varied : 90/10; 85/15; 80/20; 75/25; 70/30 and65/35 phr. Mixing process between NBR/PVC with additive used a two roll mill within atemperature of 60º - 80 ºC, the vulcanization process used a hydraulic press at a temperature of170 oC and pressure of 150 kg/cm2. The physical properties were evaluated including tensilestrength, elongation at break, hardness, before and after aging, hardness after immersion inisooctane and swelling while analysis of functional groups was also carried out by method ofFourier Transform Infrared Spectrophotometer (FTIR). The result of the best vulcanized wascharacterized by tensile strength 188.93 kg/cm2, the change of tensile strength after aging 2.50%,elongation at break of 400%, the change of elongation at break after aging was 12.5%, hardness75 shore A, the change of hardness after aging 0%, the change of hardness after immersion inisooctane 1.3%, swelling 0.8% and functional group of vulcanisate was indicated by new peak(OH) at wave band of 3468 cm-1. Those formula met the requirements of the technicalspecifications of ASTM D 2000 seal O-ring.Keywords: O-ring rubber seals, NBR, PVC, physical properties, functional groupABSTRAKTujuan penelitian ini adalah untuk mengetahui sifat fisika dan gugus fungsi karet seal Oringyang dibuat dari bahan termoplastik elastomer campuran NBR dan PVC. KomposisiNBR/PVC divariasi berturut-turut 90/10; 85/15; 80/20; 75/25; 70/30 dan 65/35 phr.Pencampuran NBR/PVC dengan bahan tambahan (aditive) menggunakan two roll mill pada suhu60º-80ºC, proses vulkanisasi menggunakan hydraulic press pada suhu 170 ºC dan tekanan 150kg/cm2. Pengujian sifat fisika karet seal O-ring meliputi tegangan putus, perpanjangan putus,kekerasan sebelum dan sesudah aging, kekerasan setelah perendaman dalam isooktan, swellingdan dilakukan juga analisis gugus fungsi dengan Fourier Transform Infrared Spectrophotometer(FTIR). Hasil uji vulkanisat terbaik sebagai berikut: tegangan putus 188,93 kg/cm2, perubahantegangan putus sesudah aging 2,50%, perpanjangan putus 400%, perubahan perpanjangan putussesudah aging 12,5%, kekerasan 75 shore A, perubahan kekerasan sesudah aging 0%, perubahankekerasan sesudah perendaman dalam isooktan 1,3%, swelling 0,8% dan muncul gugusfungsional baru OH pada bilangan gelombang 3468 cm-1. Karet seal O-ring tersebut memenuhipersyaratan ASTM D 2000 tentang spesifikasi teknis seal O-ring.Kata kunci: seal O-ring, NBR, PVC, sifat fisika, gugus fungsi

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