Pemanfaatan karet riklim dari skrap rubber roll untuk kompon sol sepatu - Setyowati, Penny; Pramono, Pramono; Supriyanto, Supriyanto (Majalah Kulit, Karet, dan Plastik, 2006)
The objective of the research was to study the effect of the used reclaim rubber from scrab rubber roll as a rubber substitution at rubber compounding for shoe sole production. The reclaime rubber was made by mixing between 100 part scrab rubber roll, 30 part reclaiming oil and 2 part reclaiming agent. The mixture was aged to swelling process for 24 hours and devulcanization was conducted at 1500C for 1.5 hours. Properties of the reclaim rubber were identified such as tension at break 46.55 kg/cm2, elongation at break 136.22%, hardness Shore A 52.8, acetone extract 30.4% and polymer contain 36.41%. The rubber compound was made by using special natural rubber of RSS I (Ribbed Smoke Sheet I) mixed with reclaim rubber at ratio of 100/0, 90/10, 80/20, 70/30, 60/40 and 50/50 phr (part hundred rubber) respectively and was also added additives. The mixing was conducted by using mixing mill at 400-600C for 50 minutes. The compound was concluded that the composition between new rubber RSS I and reclaim at the ratio 70/30 has obtained the most favorable physical properties, with respected testing result of tention at break 85.5 kg/cm2, elongation at break 195.3%, hardness 72.2 shore A, tear resistance 42 kg/cm2, permanent set at 50% elongation 0.27%, density 1.39 g/cm3, Grazelli abration resistance 4.05 mm3/kgm and flexing resistance at 150 kcs did not break. However, the physical properties of the compound was able to meet the SNI 12-0778-1989 class C except the abration resistance.  Keyword : reclaim, rubber roll, compound rubber, shoes sole   ABSTRAK Penelitian ini bertujuan untuk mempelajari pengaruh penggunaan karet riklim yang berasal dari skrap roll karet sebagai substitusi karet mentah pada pembuatan kompon karet untuk sol sepatu. Karet riklim dibuat dari skrap rubber roll 100 bb (bagian berat) dicampur dengan reclaiming oil 30 bb dan reclaiming agent 2 bb dalam mixing mill, campuran tersebut didiamkan selama 24 jam untuk proses penggembungan (swelling) kemudian didevulkanisasi pada suhu 1500C selama 1,5 jam. Karet riklim yang dihasilkan mempunyai sifat tegangan putus 46,55 kg/cm2, perpanjangan putus 136,22%, kekerasan 52,8 Shore A dan kandungan ekstrak aseton 30,4% serta kandungan polimer sebesar 36,41%. Kompon karet sol sepatu dibuat dari campuran karet alam Ribbed Smoke Sheets I (RSS I) dan karet riklim pada perbandingan berturut-turut 100/0 per hundred rubber (phr), 90/10 phr, 80/20 phr, 70/30 phr, 60/40 phr, 50/50 phr dengan bahan aditip pada jumlah tertentu. Pencampuran dilakukan dengan mixing mill kapasitas 2 kg, suhu 40-600C dan waktu 50 menit. Kompon yang diperoleh diuji sifat fisika vulkanisatnya dan hasilnya menunjukkan bahwa pada komposisi RSSI/riklim 70/30 phr merupakan komposisi terbaik dengan hasil uji fisika tegangan putus 85,5 kg/cm2, perpanjangan putus 195,3%, kekerasan 72,2 shore A, ketahanan sobek 42 kg/cm2, perpanjangan tetap (50%) 0,27 %, berat jenis 1,39 g/cm3, ketahanan kikis Grasselli 4,05 mm3/kg. m dan ketahanan retak lentur 150 kcs. Sifat-sifat fisis kompon dapat memenuhi syarat SNI 12-0778-1989 : Sol karet cetak untuk klas C kecuali sifat ketahanan kikisnya. Kata Kunci : karet riklim, rubber roll, kompon karet, sol sepatu.