Mechanical and Thermal Properties of Roselle Fibre Reinforced Vinyl Ester Composites

Abstract

Roselle (Hibiscus sabdariffa L.) bast fibre reinforced vinyl ester (VE) was prepared using a hand lay-up method and an internal mixer. The composite samples were prepared under two different parameters: with various fibre contents; and without fibre (neat VE). The mechanical properties (tensile and impact strength) and thermal properties were investigated. The morphological properties of impact fracture samples were studied using a scanning electron microscope (SEM). Roselle fibre reinforced VE (RFVE) composites showed increased tensile strength and tensile modulus. The highest tensile strength and modulus were at 20vt% fibre loading. However, impact strength decreased as the fibre loading increased. SEM showed that there was good fibre/matrix adhesion and fibre dispersion for 20% fibre loading, which was reflected in the good tensile strength properties. However, fibre agglomeration was seen at higher fibre loads. The results from thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG) showed three major degradations of the RFVE, which were the loss of moisture content, degradation of hemicelluloses, and degradation of cellulose. The thermal analysis showed enhancements in the residual content of the composite materials, thereby improving the thermal stability. However, there was no major difference seen in the degradation temperature.

Ballistic impact velocity response of carbon fibre reinforced aluminium alloy laminates for aero-engine

“…Similar result has also been observed in Ref. [39], where the impact strength of different load percentages of Roselle fibre was investigated. There are some factors that affect the impact strength of the composites after fire test, which are poor adhesion, poor interfacial bonding between the matrix and fibre, and also stress concentration at the end of fibre.…”

Fire behavioural and mechanical properties of carbon fibre reinforced aluminium laminate composites for aero-engine

“…CARALL2 was 66.67%, 83.32% and 33.33% higher than CAR-ALL4, CARALL3 and CARALL1 respectively in terms of impact strength on low velocity, for total energy absorbed before crack begins in the composite. More delamination was observed on CARALL1 due to the number of aluminium alloy used in the composite that showed lower surface dissipation of energy, the result coincided with the results obtained using glass fibre reinforced plastic and other investigations [9,[46][47][48].…”

Characteristic of thermoplastics corn starch composite reinforced short pineapple leaf fibre by using laminates method

“…Good tensile strength result is depending on the effective and uniform stress distribution between the fibre and matrix. Fibre also acts as the reinforced material which can stop crack propagation [34]. The enhancement of tensile strength and modulus clearly shows that the fibre has higher tensile properties than neat matrix.…”

“…This observation is similar to previous studies by Nadlene Razali et al [34] on mechanical and thermal properties of roselle fibre reinforced vinyl ester composites where the higher fibre loading developed more fibre to fibre contact, compared with the fibre and matrix. The composites failed at a small load, which indicated a low tensile strength due to the weak interfacial bonding between fibre and matrix [34].…”