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Abstrak :
EPDM (Ethylene propylene diene monomer) is one of synthetic rubber that widely used in automotive. It must be vulcanized and added by other materials before used. The aim of this study is to investigate the effect of vulcanization system and the addition of carbon black (CB) to the mechanical properties and swelling characteristic of EPDM. This research used three vulcanization system: conventional vulcanization (CV), efficient vulcanization (EV), and semi-efficient vulcanization (SEV) with the variation of carbon black 50, 60, and 70 phr (per hundred resin). This research showed that EV system resulted faster vulcanization time and lower delta torque than SEV and CV systems. This system also performed the highest tensile strength, elongation, and tear strength, while SEV system resulted the highest hardness. Furthermore, the conventional vulcanization system resulted the lowest swelling index.

Abstrak :
The land area and production of rubber on smallholder rubber plantations contribute to about 85% and 81% of national rubber production, respectively. Based on this, having technology to utilize vulcanized natural rubber latex (NRL) in a way that is simple, inexpensive, energy-saving, environmentally friendly, and according to the quality standards of the processing of NRL is important. The purpose of the current research is to design of a prototype photoreactor ultraviolet light-emitting diodes (UV-LEDs) for the vulcanization of NRL that is irradiated (VNRLI) to produce NRL-irradiated free carcinogens and protein allergens. The methodology used is the technological development of a prototype photoreactor with an UV-mercury irradiator that located in a vertical cylindrical glass column with the capacity of VNRLI about 249.2 tons/year. The development of technologies applied to increase the capacity of VNRLI by enlarging the area of thin NRL films to be irradiated with UV-A rays derived from UV-LED irradiators that are more energy-efficient, long-life, and environmentally friendly than UV-mercury irradiators. The results allowed for the design of a prototype photoreactor UV-LEDs to process feed NRL with the capacity VNRLI about 522 tons/year. The UV-LED photoreactor prototype design results show that the UV-LED photoreactor prototype is ready to test the VNRLI process function that can produce NRL- irradiated free carcinogen and protein allergens.

Abstrak :
Perkembangan pemakaian karet yang terus meningkat akan meningkatkan pula limbah. Hal ini yang akan menjadi salah satu persoalan yang serius karena jika limbah hasil produksi ini tidak terkelola dengan baik. Dalam konteks ini, dilakukan penelitian daur ulang limbah dengan cara degradasi mekanis. Limbah digunakan kembali dalam formulasi kompon karet sebagai bahan pengisi dengan variasi 0; 7,5; 15; 22,5; 30; 37,5 PHR. Hasil kompon karet tersebut akan diuji sifat mekanik, sifat gugus fungsi dan sifat struktur mikrosopik. Berdasarkan hasil uji mekanik diperoleh penurunan kekuatan tarik sebesar 5,56 – 22,97%, perpanjangan putus sebesar 1,95 – 35,88% dan ketahanan kikis sebesar 5,72 – 57,31% sedangkan nilai mekanik lainnya mengalami kenaikan, yaitu kekerasan sebesar 1,61 – 3,17%, berat jenis sebesar 0,14 – 0,95% dan kekuatan sobek sebesar 7,41 – 17,14%. Berdasarkan hasil FTIR, kompon karet baik tanpa maupun penambahan limbah terlihat bahwa tidak menunjukkan adanya gugus fungsi baru, tetapi jika diamati dapat diketahui bahwa ada perubahan intensitas dan pergeseran spektrum pada kompon karet yang ditambahkan limbah karet. Berdasarkan hasil uji SEM, semakin banyak penambahan limbah pada kompon karet maka semakin banyak rongga (pori-pori) udara dan permukaan akan lebih kasar. Dari hasil pengujian sifat mekanik limbah karet pada kompon karet, diperoleh nilai-nilai yang masuk persyaratan ASTM dari formula 1 sampai dengan formula 4 dengan penambahan limbah karet ke dalam kompon karet sebesar 0; 7,5; 15 dan 22,5 PHR. ......The development of rubber usage that continues to increase will also increase waste. This will become one of the serious problems because if the waste is not managed properly. In this context, waste recycling research is carried out by vb mechanical degradation. Waste rubber is reused in the rubber compound formulation as filler with variation 0; 7.5; 15; 22.5; 30; 37.5 PHR. The results of the rubber compound will be tested for mechanical properties, functional groups and microscopic structure properties. Based on the results of mechanical tests obtained a decrease in tensile strength of 5.56 – 22.97%, elongation at break of 1.95 – 35.88% and abrasion resistance of 5.72 – 57.31% while other mechanical values have increased, namely hardness of 1.61 – 3.17%, specific gravity of 0.14 – 0.95% and tear strength of 7.41 – 17.14%. Based on the results of FTIR, both rubber compounds and waste addition does not show that there is no new functional group, but if it is observed it can be seen that there is a change in intensity and spectrum shifts in the rubber compound added with rubber waste. Based on SEM test results, the more waste added to the rubber compound, the more cavities (pores) of air and the surface will be more rough. From the results of testing the mechanical properties of rubber waste on rubber compound, obtained values that meet ASTM requirements from 1st until 4th formula with the addition of rubber waste by 0; 7.5; 15 and 22.5 PHR.

Abstrak :
Indonesia merupakan negara dengan produksi karet terbesar kedua didunia. Bahan baku karet paling banyak digunakan umumnya pada industri otomotif khususnya aplikasi ban kendaraan. Ban diharuskan memiliki sifat mekanik yang tinggi pada aplikasinya. Penambahan pengisi umum dipakai untuk meningkatkan sifat mekanik pada aplikasi kompon ban. Pengisi yang umum dipakai ialah karbon hitam dan silika namun terkendala pada biaya yang mahal pada material tersebut. Serat Tandan Kosong Kelapa Sawit(TKKS) berpotensi menjadi salah satu pengisi alternatif. Namun, Sifat permukaan serat TKKS yang sangat polar menjadi kendala dalam kompatibilitasnya terhadap karet alam yang non polar sehingga diperlukan coupling agent dalam aplikasinya. Hibrida karet alam-selulosa dapat menjadi agen pengikat antara karet alam dengan serat TKKS. Akan tetapi dalam pemrosesan karet setiap zat yang ditambahkan akan mempengaruhi proses vulkanisasi. Investigasi perilaku alir dari proses vulkanisasi dan kompatibilitas karet alam-serat TKKS yang ditambahkan coupling agent karet alam selulosa telah dilakukan. Hasil menunjukan penambahan coupling agent meningkatkan absorpsi ikatan hidrogen O-H serta menurunkan fiber pull-out dan meningkatkan distribusi dan dispersi serat. Perilaku alir menunjukan peningkatan torsi maksimum serta penurunan waktu scorch dan waktu optimal pematangan serta didapatkan optimum pada pemakaian suhu vulkanisasi 150°C dan coupling agent karet alam-selulosa sebesar 2 phr. Nilai konstanta laju reaksi menunjukkan kenaikan serta energi aktivasi mengalami penurunan terhadap temperatur dan komposisi coupling agent karet alam-selulosa. ......Indonesia is the second largest natural rubber producer in the world. Raw material of natural rubber found most of its application in automotive industries espesially the main material of vehicle tires. The tires require good mechanical properties in its application. Addition of filler is a common method to enhance the mechanical strength in rubber mostly utilizing carbon black and silica. Another alternative is by using oil palm empty fruit bunch(OPEFB) as the filler. However, OPEFB has a polar characteristic on its surface, thus reducing its compatibilty with natural rubber significantly. Natural rubber-cellulose hybrid shows possibility to be utilized. However, in processing rubber, each added substance will affect the vulcanization process. Investigation of flow behavior of the vulcanization process and compatibility of natural rubber-fiber OPEFB which was added to the narutral rubber grafted cellulose coupling agent was carried out. The results show that the addition of coupling agents increases the absorption of O-H hydrogen bonds and lowers fiber pull-out and increases fiber dispersion. Flow behavior showed an increase in maximum torque and a decrease in scorch time and optimal maturation time and was obtained optimum at the use of 150°C vulcanization temperature and latex-cellulose coupling agent of 2 phr. The value of the reaction rate constant increase and the activation energy decreases with temperature and the composition of the latex-cellulose coupling agent.