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All Journal Majalah Kulit, Karet, dan Plastik
Umi Reza Lestari
Center for Leather, Rubber & Plastics
Engineering

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Application of Tegeran (Maclura cochinchinensis) bark as natural tanning agent for the quality of tilapia fish skin Gresy Griyanitasari; Iwan Fajar Pahlawan; Umi Reza Lestari
Majalah Kulit, Karet, dan Plastik Vol 35, No 2 (2019): 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.v35i2.5503

Abstract

Chrome is a tanning material that is very harmful to the environment hence its role is being replaced with vegetable tanning materials. One of the natural ingredients that contain tannin is Tegeran (M. cochinchinensis) wood. The aim of this study was to determine the effect of M. cochinchinensis as natural tanning agent for tilapia fish skin. Tannin contained in the M. cochinchinensis was being extracted using three solvents: water, ethanol, and water-ethanol (1:1). The composition of the material and the solvent was 1:4. It was heated in the waterbath at temperature 70 °C for 3 hours. The results showed that the use of M. cochinchinensis as natural tanning agent could at once gave unique color to the tanned fish skin. The average of shrinkage temperature was 78.11°C. Leather tanned with M. cochinchinensis that was extracted with water showed higher value of tensile strength and tear strength than those with ethanol and water-ethanol.
EVA/starch/POE composite for footwear material: How the chemical composition affects its properties compared to standards Umi Reza Lestari; Gunawan Priambodo; Dwi Wahini Nurhajati
Majalah Kulit, Karet, dan Plastik Vol 37, No 2 (2021): 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.v37i2.7449

Abstract

The usage of biodegradable foam material in footwear components has positive impacts on environmental sustainability when disposed into landfills. This study was aimed to investigate the effects of polyolefin elastomer (POE) on its properties of foamed EVA/cassava starch composites compared to standards. Foamed EVA/cassava starch composites were prepared by mixing EVA, cassava starch, and additives using a two-roll mill laboratory scale. Content of POE was varied 10-20 phr. The ratios of EVA/cassava starch were varied from 90/10; 80/20; 70/30; and 60/40. Effects of POE were characterized its density, tensile properties, tear strength, permanent set, abrasion resistance, flex resistance, morphology, and biodegradability. It was found that the increase of POE content in EVA/starch composites increased the density and abrassion resistance, but decreased the tensile strength, elongation at break, and permanent set properties. The best formula of foamed EVA/cassava starch/POE composites for footwear materials contains EVA 80 phr, starch 20 phr and POE 20 phr with density 0.983 g/cm³, tensile strength 22.27 kg/ cm², elongation at break 645.67%, tear strength 9.42 N/mm, volume loss 88.907 mm, no crack when flexed 150 kcs. These results met the requirements of SNI 0778:2009-Sol Karet Cetak for quality classifcation 3 of outsoles. The foamed composite containing POE20 has denser morphology than POE10, while the addition of POE has no signifcance in weight loss after burial test
Co-Authors Dwi Wahini Nurhajati Gresy Griyanitasari Gunawan Priambodo Iwan Fajar Pahlawan