Sains Malaysiana 36(2):  183-188 (2007)

Penyediaan Adunan LDPE/LNR Melalui Penyebaran Emulsi

(Preparation of LDPE/LNR Blend Via Emulsion Dispersion)

Rusli Daik & Yee Lee Ching

Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

Diserahkan: 5 Januari 2007 / Diterima: 27 Februari 2007 

ABSTRAK

Adunan polietilena berketumpatan rendah (LDPE)/getah asli cecair (LNR) dalam komposisi 100LDPE/0LNR, 70LDPE/30LNR, 60LDPE/40LNR dan 40LDPE/60LNR telah dihasilkan melalui penyebaran emulsi LDPE dan LNR.. LNR diperolehi melalui tindak balas pemekaan fotokimia ke atas getah asli (NR) dan emulsi LNR disediakan dengan menggunakan natrium dodesil sulfat (SDS) sebagai agen pengemulsi dan 1-heksanol sebagai ko-pengemulsi. Emulsi LDPE dihasilkan dengan cara yang sama menggunakan larutan LDPE dalam karbon tetraklorida, SDS dan 1-heksanol. Adunan LDPE/LNR  disediakan melalui pencampuran emulsi LNR dan LDPE. Sifat mekanik adunan LDPE/LNR dianalisis melalui ujian regangan, hentaman dan kekerasan. Sifat mekanik optimum diperhatikan bagi adunan dengan komposisi 60LDPE/40LNR yang memberi nilai tegasan dan terikan yang maksimum. Suhu peralihan kaca, T_g, seperti yang diperolehi daripada analisis kalorimetri imbasan pembezaan (DSC) menunjukkan adunan yang dihasilkan adalah homogen. Kajian morfologi yang dilakukan dengan menggunakan mikroskop imbasan elektron (SEM) juga menunjukkan kehomogenan adunan yang dihasilkan. 

Kata kunci:Getah asli cecair; adunan; penyebaran emulsi

ABSTRACT

Low density polyethylene (LDPE)/ liquid natural rubber (LNR) blends with the composition of 100LDPE/0LNR, 70LDPE/30LNR, 60LDPE/40LNR and 40LDPE/60LNR were prepared via dispersion of LDPE and LNR emulsion. LNR was obtained via photochemical sensitization of natural rubber (NR). Emulsion of LNR was prepared by using sodium dodecyl sulfate (SDS) and 1-hexanol as the emulsifier and co- emulsifier respectively. Emulsion of LDPE was prepared in the same way by using LDPE solution in carbon tetrachloride, SDS and 1-hexanol. LDPE/LNR blends were prepared via mixing of LNR and LDPE emulsions. Mechanical properties of the blends were analyzed by tensile, hardness and impact test. Optimum mechanical properties were observed for composite with composition of 60LDPE/40LNR that showed the maximum value of stress and strain. The glass transition temperature, T_g, of the blends as obtained from differential scanning calorimetric (DSC) showed that the blends were homogeneous. Morphology study by using scanning electron microscopy (SEM) also indicates the homogeneity of LDPE/LNR blends produced.

Keywords: Liquid natural rubber; blend; emulsion dispersion

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