Sains Malaysiana 32: 57-65 (2003)                                                                                                Sains Fizis dan Gunaan /

Physical & Applied Science

 

Reologi Adunan Getah Asli dan Polietilena Linear

Berketumpatan Rendah Berpengisi Karbon Hitam

(Rheology of natural rubber and carbon black folled linear

low-density polyethylene blends)

 

 

Azizan Ahmad

Kolej Kejuruteraan

Universiti Tenaga Nasional 43000 Kajang

Selangor D.E., Malaysia

 

Dahlan Hj. Mohd.

Institut Penyelidikan Teknologi Nuklear (MINT)

Bangi 43000 Kajang

Selangor D.E., Malaysia

 

Ibrahim Abdullah

Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia

43600 UKM Bangi

Selangor D.E., Malaysia

 

 

ABSTRAK

 

Kajian reologi dan hubungannya dengan morfologi telah dilakukan ke atas adunan getah asli (NR)/ polietilena linear berketumpatan rendah (LLDPE) mengikut nisbah berat sebanyak 60/40. Getah asli cecair (LNR) telah digunakan sebagai pengserasi adunan NR/LLDPE dan karbon hitam (CR) digunakan sebagai pengisi penguat adunan. Proses pengadunan dilakukan pada suhu 140°C, kelajuan rotor 50 ppm dan selama 15 minit. Perubahan reologi pengadunan ditunjukkan oleh plastogram tork berfungsi masa adunan. Tork bagi adunan yang mengandungi getah asli cecair (LNR) semakin meningkat dengan masa berbanding dengan adunan tanpa LNR. Fenomena tersebut berlaku disebabkan oleh LNR telah bertindak sebagai agen pengserasi yang baik bagi adunan NR/LLDPE. Penambahan karbon hitam ke dalam adunan telah meningkatkan lagi interaksi antara NR dan LLDPE dan seterusnya meningkatkan kelikatan adunan. Kelikatan adunan NR/LNR/LLDPE/CB lebih tinggi berbanding adunan NR/LLDPE/CB. Disamping itu juga, morfologi yang mengandungi LNR adalah lebih baik berbanding dengan adunan tanpa LNR. Kesimpulannya terdapat hubungan yang jelas di antara reologi dan morfologi bagi adunan tersebut.

 

 

ABSTRACT

 

Studies on rheology and morphological properties of NR/LLDPE (60:40) blends were carried out. Liquid natural rubber (LNR) and carbon black (CR) were used as compatibilizer and reinforcement filler in NR/LLDPE blends, respectively. The blending process was carried out by using Haake Rheomix at l40oC, 15 minute mixing time and a rotor speed of 50 rpm. Rheological properties were observed from torque plastogram versus mixing time. Torque of samples with LNR increase with time compared to uncompatibilized samples. It was believed that LNR acting as a compatibilizer in NR/LLDPE blend. Torque increase with increasing amounts of carbon black loaded in the samples. Viscosities of the sample increased with the introduction of carbon black due to the reinforcement between carbon black and the polymer matrix. The viscosity of NR/LNR/LLDPE is higher than the NR/LLDPE blend loaded with carbon black. In conclusion, the addition of LNR and carbon black affected the rheological and morphological properties of NR/LLDPE blends.

 

 

RUJUKAN/REFERENCES

 

Clarke, J., Freakley, P.K. 1994.  Reduction in Viscosity of on SBR Compound Caused, by Mastication and Disagglomeration During Mixing. Rubber Chemistry and Technology 67: 700-715.

Dahlan, H.M, Khairul Zaman, M.D. & Ibrahim, A. 2000. Liquid Natural Rubber (LNR) as a Compatibilizer in NR/LLDPE Blends. Journal of Applied Polymer Science 78: 776-1782.

De, S.K. & Anil, K. B. 1990. Thermoplastic Elastomers From Rubber-Plastic Blend. Ellis Horwood Series in Polymer Science Technology, 71-101.

Donnet, J-B., Bansal, R.C. & Wang, M-J. 1993. Carbon Black: Science and Technol­ogy, 2nd ed. New York, 289-345.

Herd, Ch.R. & Bomo, F. 1995. Phase Distribution Analysis and Properties of Carbon Black Filled Elastomer Blends. KGK Kautschuk Gummi Kunststoffe 48. Jahrgang, Nr.9 : 588-599.

Ibrahim, A., Sahrim, A. & Che Som, S. 1995. Blending of Natural Rubber with Linear Low-Density Polyethylene. Journal of Applied Polymer Science, 58: 1125-1133.

Javier, G. M., Luis M.Q., Alfredo, M., Octavio, M. 2001. Carbon Black-Filled PET/ HDPE Blends: Effect of the CB Structure on Rheological and Electric Properties. Journal of Applied Polymer Science 81: 562-569.

Katbab, A.A., Nazockdast, H., Bazgir, S. 2000. Carbon Black-Reinforced Dynami­cally Cured EPDMlPP Thermoplastic Elastomers.I. Morphology, Rheology, and Dynamic Mechanical Properties. Journal of Applied Polymer Science, 75: 1127­-1137.

Kraus, G. 1965. Interactions of Elastomers and Reinforcing Fillers. Rubber Chemistry and Technology 38: 1070-1113.

Mallick, A., Tripathy, D. K. & De, S.K. 1993. Effect of Reinforcing Carbon Black Filler on Thermally Induced Crosslinking of Polyacrylic Acid-Epoxidized Natu­ral Rubber Blend. Journal of Applied Polymer Science 50: 1627-1634.

Mallick, A., Tripathy, D. K. & De, S.K. 1994. Thermally Induced Crosslinking between Polyacrylic Acid and Epoxidized Natural Rubber. III. Effect of Carbon Black Filler and Mixer Rotor Speed. Journal of Applied Polymer Science 53: 1477-1490.

 

 
sebelumnya