Pengaruh Ukuran Ketebalan Karet Alam Terhadap Nilai Plastisitas Retensi Indeks (PRI) pada Karet Sir (Standart Indonesian Rubber) 20 di PT. Rubber Hock Lie Sunggal Sumatera Utara

Abstract

Rubber with a low Plasticity Retention Index (PRI) is more likely to oxidize into soft rubber, whereas rubber with a high PRI value has an oxidation-resistant molecular chain. The initial plasticity value also has an effect on PRI, which is influenced by two opposite factors: the value of the rubber's hardening, which goes up, and the value of the rubber's oxidation, which goes down. Using a Wallace Plastimeter, the Plasticity Retention Index is a straightforward test used to determine the elastic resistance to degradation caused by oxidation at high temperatures or wear and tear. The Wallace Plastimeter method was used to analyze the PRI value on crumb rubber, and the results were obtained. The PRI value for samples measuring 2.8 mm was 63%, the PRI value for samples measuring 3.0 mm was 68%, the PRI value for samples measuring 3.2 mm was 69%, the PRI value for samples measuring 3.4 mm was 70%, the PRI value for samples measuring 3.6 mm was 70%, the PRI value for samples measuring 3.8 mm was 71%, the PRI value for samples measuring 4.0 mm was 72%, the PRI value for samples measuring 4.2 The worth of the Versatility Maintenance File (PRI) incredibly impacts the nature of elastic on the grounds that the more prominent the worth created, the better the opposition of elastic to debasement at high temperatures. The Pliancy Maintenance List (PRI) got during testing has met the SNI 1970: 2017 Standard Elastic File (SIR) by taking the PRI worth of 40%. During the testing, the Plasticity Retention Index was found to be between 63% and 77%.