Sains Ma1aysiana 27: 119-126 (1998)                                                                          Sains Fizis dan Gunaan/

                                                                                                                                     Physical and Applied Sciences

Kajian Adunan Terner Getah Asli-Polipropilena-

Polietilena Berketumpatan Rendah Linear

(A study on ternary blend of natural rubber-polypropylene-linear

low density polyethylene)

Sahrim Ahmad, Ibrahim Abdullah & Che Som Sulaiman

Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor, D.E

ABSTRAK

Adunan terner yang terdiri dari getah asli (NR), polipropilena (PP) dan polietilena berketumpatan rendah linear (LWPE) dengan getah asli cecair (LNR) sebagai pengserasi telah disediakan dan dinilai secara jizikal. Sifat jizikal dan mekanik adunan didapati bergantung kepada komposisi dan keadaan pemprosesan. Untuk adunan 50% NR, keadaan pemprosesan temoplastik adalah suhu, 165 - 170ºC, kelajuan rotor, 40 rpm dan masa pemprosesan, 10 minit. Tegasan bahan menu run secara mendadak apabila LLDPE dicampur kepada adunan NR/PP dan ke paras minimum apabila komposisi PP dan LLDPE menjadi sama. Manakala terikan bahan meningkat hampir linear dengan komposisi LWPE. Peranan LNR sebagai pengserasi hanya berkesan dalam fasa NR-plastik dan LNR tidak memberi sebarang pengaruh ke atas taburan fasa dalam campuran LLDPE-PP.

ABSTRACT

A ternary blend comprising of natural rubber (NR), polypropylene (PP) and linear low density polyethylene with liquid natural rubber (LNR) as a compatibiliser was prepared and evaluated physically. The physical and mechanical properties of the blend were found to depend on the composition and processing conditions. For a 50% NR blend, the thermoplastic process­ing conditions were temperature, 165 - 170ºC, rotor speed, 40 rpm and processing time, 10 minutes. The stress of the material decreased signifi­cantly on addition of LLDPE into the NR/PP blend and reached a minimum when the composition of PP and LWPE were equal. However the material strain increased almost linearly with the amount of LWPE added. The role of LNR as a compatibiliser was only effective in NR/plastic interface and LNR had no influence on the phase distribution in the LLDPE-PP mixture.

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