Dimethyl ether (DME) is a type of renewable energy that could replace the use of fossil fuel in Indonesia. Nevertheless, DME can cause degradation of rubber-based materials. Therefore, the performance of rubber that has been degraded by DME must be improved. This research study aims are to determine the degradation characteristics of modified vulcanized natural rubber in a DME environment. The effect of the filler (carbon black) and plasticizer (minarex-B) components of vulcanized natural rubber was examined. The vulcanized rubber samples were comprised of 10, 30, and 60 parts per hundred rubbers (phr) of filler and 0, 10 and 20 phr of plasticizer. The degradation of the mass and mechanical properties of the rubber were investigated. Degradation testing was conducted by immersing the samples inside a pressure vessel that was filled with the liquid phase of DME. The results indicate that the increasing of the filler composition reduces the impact of degradation, while the increasing of the plasticizer composition has the opposite effect. The plasticizer is needed to distribute the filler to all parts of the rubber. Consequently, a filler composition of 30 phr and a plasticizer composition of 10 phr provide a vulcanized natural rubber with optional protection against the degradation caused by DME. The characteristics of natural rubber, as measured by Fourier Transform Infra-Red Spectroscopy (FTIR) proved that DME does not damage the structure of the polymer chains, although DME may react with some ingredients in the rubber that have a similar polarity.
PT Heksatex Indah adalah perusahaan yang bergerak di bidang tekstil rajut lusi. Masalah yang dihadapi oleh perusahaan ini adalah operator mengalami kesulitan dalam melakukan aktivitas pemasukan, pencarian, dan pengeluaran kain dari/ke gudang pra-proses (kain grey) dikarenakan kain diletakkan di area gang dan banyak jenis kain yang sama berada di beberapa lokasi penyimpanan. Dalam memecahkan permasalahan yang dihadapi perusahaan, digunakan metode class-based storage dalam merancang tata letak gudang yang baru dengan menggunakan alat penyimpanan kain usulan yang sudah dimodifikasi dari alat penyimpanan kain sebelumnya. Selain itu, diusulkan pula penggunaan alat material handling baru, yaitu trolley kecil, untuk memudahkan kerja operator supaya tidak membawa gulungan kain satu per satu. Berdasarkan hasil perhitungan, jika perusahaan menerapkan tata letak usulan, maka terjadi penghematan jarak rata-rata dari pintu ke lokasi penyimpanan sebesar 64,53 m dan 52,35 %. Tata letak kain usulan memiliki tata letak yang lebih rapi dan teratur dibandingkan dengan tata letak kain saat ini karena kain yang sama berada di satu lokasi dan tidak terdapat kain yang disimpan di gang yang menghalangi operator dalam melakukan aktivitasnya. Kata kunci : Class-based, Gudang, Material Handling, Kain, Jarak Rata-rata
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.