Sains Malaysiana 34(1): 57-61 (2005)

Penambahan Gentian Aramid (Twaron) dalam Adunan NR/LLDPE

dan ENR/LLDPE terhadap Sifat Mekanik Komposit

(Aramid Fibre (Twaron) Loading in NR/LLDPE and ENR/LLDPE

Blends on Mechanical Properties of the Composites)

Ishak Ahmad, Norul Azwan Din, Affendi Mohamad

Azizah Abdul Aziz & Ibrahim Abdullah

Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

ABSTRAK

Penyediaan adunan getah asli termoplastik dan getah asli terepoksida termoplastik yang diperkuat dengan gentian aramid telah dilakukan melalui proses adunan leburan. Gentian aramid yang digunakan adalah gentian pendek Twaron (Teijin-Twaron) yang dirawat dengan bahan pelekat epoksi dan resorcinolformaldehid latex (RFL). Hasil yang diperolehi menunjukkan bahawa kesan penambahan gentian aramid telah meningkatkan tegasan maksima, modulus regangan, kekuatan hentaman  dan kekerasan kedua-dua adunan tersebut tetapi menurunkan nilai terikan pada takat putus. Bagi adunan NR/LLDPE didapati komposisi gentian yang paling optima adalah pada 20%. Penambahan gentian aramid seterusnya hanya menurunkan sifat mekanik adunan. Sebaliknya bagi adunan ENR/LLDPE, didapati komposisi gentian melebihi 20% masih menunjukkan peningkatan tegasan maksima dan modulus regangan. Keputusan ini menunjukkan bahawa interaksi antaramuka gentian aramid dan matriks dalam adunan ENR/LLDPE lebih baik berbanding NR/LLDPE.

Kata kunci: Gentian aramid, adunan NR/LLDPE, adunan NR/LLDPE

ABSTRACT

Blends of fiber-reinforced rubber (FRR) based on natural rubber-thermoplastic (NR/LLDPE) and epoxidized natural rubber ­thermoplastic (ENR/LLDPE) reinforced by aramid fibre have been done using melt blending process. Twaron aramid fibres (Teijin-Twaron) used in this project were treated with epoxy adhesion activated and resorcinol formaldehyde latex (RFL). It was found that with increasing amount of aramid fibre led to increase the maximum stress, tensile modulus, impact strength and hardness of the composites while the strain at break decreased rapidly. The results show that the optimum composition of filler loading in NR/LLDPE blend is 20%. However, in the case of the ENR/LLDPE composite, the tensile strength and modulus increase with increasing amount of the fibre above 20%. The results indicate that the interfacial adhesion between ENR/LLDPE and aramid is better than for the NR/LLDPE.

Keywords: Aramid Fibre, NR/LLDPE blend, ENR/LLDPE blend  

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