Latex properties of several recommended clones, 1 : recommended rubber clones 1988-1990

English. A research on the technical properties of latex several recommended clones was carried out for one year. The properties investigated were dry rubber content (DRC), ash content, volatile matter content, wallace plasticity (Po), Mooney viscosity (VR), plasticity retention index (PRI), lovibond index, pH of field latex, coagulation pH, physical stability and metals content of latex i.e. : magnesium, calsium, copper, manganese. The results indicated that DRC ranged from 34-41 percent, ash content 0.31-0.41 percent, volatile matter content 0,42-0,53 percent, Po 30-50, VR 55-85, PRI 72-97, lovibond index 3,2-5,0, pH of field latex 6.30-6.76, coagulation pH 4,30-4,50 and physical stability of latex 23-36 seconds. Metals content of latex and its properties varied with time and were influenced by season. In addition, the colour of latex and coagulum which was visually observed is also discussed here.

Indonesian. Suatu penelitian terhadap sifat-sifat teknis latexs berbagai klon anjuran telah dilakukan selama satu tahun. Sifat yang diamati meliputi kadar karet kering, kadar abu, kadar zat menguap, plastisitas awal, viskositas Mooney, indeks ketahanan plastisitas, indeks lovibond, pH lateks kebun, pH penggumpalan, ketahanan fisika, dan kandungan logam dalam lateks, yaitu magnesium, kalsium, tembaga dan mangan lateks. Hasil penelitian menunjukkan bahwa kadar karet kering berkisar 34-41 persen, kadar abu 0,31-0,41 persen, kadar zat menguap 0,42-0,53 persen, plastisitas awal 30-50, viskositas Mooeny 55-85, indeks ketahanan plastisitas 72-97, indeks lovibond 3,2-5,0, pH lateks kebun 6,30-6,76, pH penggumpalan 4,30-4,50, dan ketahan fisika lateks 23-36 detik. Kandungan logam-logam lateks dan sifat-sifat karet tersebut bervariasi sepanjang tahun dan dipengaruhi oleh musim. Warna lateks dan koagulum secara visual juga dibahas dalam tulisan ini.