Maleated Natural Rubber as a Coupling Agent for Recycled High Density Polyethylene/Natural Rubber/Kenaf Powder Biocomposites

Kenaf powder (KP) was incorporated into recycled high density polyethylene (rHDPE)/natural rubber (NR) blend using an internal mixer at 165°C and rotor speed of 50 rpm. The tensile strength and elongation at break of the composites decreased, while the tensile modulus increased with increasing filler loading. The water absorption was found to increase as the filler content increased. The maleic anhydride grafted natural rubber was prepared and used to enhance the composites performance. The addition of MANR as a coupling agent improved the tensile properties of rHDPE/NR/KP biocomposites. The water absorption was also reduced with the addition of MANR.     

不同的漂剂对红麻磺化化学机械浆色度的影响

应用一种新颖的方法，研究了不同的漂剂对红麻磺化化机浆（ＳＣＭＰ）的颜色或色调的影响。结果表明，就去除纸浆的黄色调而言，ＮａＢＨ＿４和Ｈ＿２Ｏ＿２漂白是非常有效的，而效果以ＮａＢＨ＿４为最佳。ＣＨ＿３ＣＯＯＯＨ漂白浆的黄色调较深，而Ｈ＿２Ｏ＿２两段漂能获得比Ｈ＿２Ｏ＿２单段漂较浅黄色调的纸浆。     

红麻半化学浆试制牛皮箱纸板

本文论述了在实验室对红麻全杆及芯杆分别试制牛皮箱纸板的研究．研究结果表明：红麻全杆及芯杆经适宜的化学方法和工艺条件处理后，经高浓磨浆制得的半化学浆以不同的配比代替本色木浆挂面，试制的牛皮箱纸板各项技术指标均可达到国家标准要求．     

红麻全秆碱性亚钠化机浆工艺及磨木木素热学性质的研究

在已优选出来的最佳条件下，进行不同工艺路线下制取红麻全秆ＡＳＣＭＰ的研究。结果表明料片水洗再汽蒸，然后预处理，再经常压二道磨浆，所得浆料在实验室抄造出的新闻纸，各项指标均达到或超过国家Ａ级标准。通过ＰＦＩ磨研究表明红麻ＡＳＣＭＰ的适宜磨浆程度为磨至５５～６０°ＳＲ。采用ＳＥＭ观察到了浆料中潜态的存在。消潜可在６０℃下进行。用差热分析仪测定了磨木本素的玻璃化转变温度（Ｔｇ），由于木素被磺化，Ｔｇ下降了３．６７℃。     

红麻制浆造纸的研究与应用

就红麻制浆造纸的研究和应用现状进行了综述．涉及的主要方面包括红麻的原料特性，红麻研制化学浆，红麻研制高得率浆及红麻在生产上的应用情况．概述了红麻资源情况和红麻制浆废液的治理．     

Quasi-static penetration and ballistic properties of kenaf–aramid hybrid composites

In this research, quasi-static penetration and ballistic properties of non-woven kenaf fibres/Kevlar epoxy hybrid laminates with thicknesses ranging from 3.1 mm to 10.8 mm by hard projectile at normal incidence have been experimentally investigated. Hybrid composites were fabricated by hand lay-up technique in a mould and cured at room temperature for 24 h by static load. Hybrid composites consist of Kevlar layers and non-woven kenaf layers at three different configurations, i.e. kenaf at the innermost layers, outermost layers and at the alternating layers. Kevlar/epoxy and kenaf/epoxy composites were also fabricated for comparison purpose. Quasi-static experiments were conducted using a tensile testing machine at the speed of 1.27 mm/min and 2.54 mm/min. Ballistic tests were conducted using 9 mm full metal jacket bullet using a powder gun at speeds varying from 172 to 339 m/s, with the initial and a residual velocity of the projectiles is measured. The tested sample was carefully examined with respect to failure modes. Results showed the effect of hybridization in term of force–displacement curves, energy dissipation and damage mechanisms for quasi-static test. Maximum force to initiate penetration is higher in hybrid composites compared to kenaf/epoxy and Kevlar/epoxy composites. Hybridization of kenaf–Kevlar resulted in a positive effect in terms of energy absorbed (penetration) and maximum load. In the case of ballistic tests, hybrid composites recorded lower ballistic limit (V₅₀) and energy absorption than the Kevlar/epoxy composite. The V₅₀ of hybrid composites with kenaf at the outermost layers is superior to other hybrid composites. These finding inspired further exploration of hybrid composite for ballistic armour spall-liner application.     

Preparation and Characterization of Kenaf Papers Reinforced with Tapioca Starch: Physicomechanical and Morphological Properties

The present study reports the preparation and characterization of kenaf papers that reinforced with tapioca starch by using the ammonium zirconium (IV) carbonate as coupling agent. The examination shows the tearing resistance, tensile strength, and Young’s modulus of the kenaf papers are enhanced with the addition of starch and coupling agent, up to 3% and 1%, respectively. Under the optimum formulation, the degree of coupling reaction is 87%. The Fourier transform infrared and morphological analyses confirm the performance enhancement of kenaf papers is achieved via the formation of chemical bonding between the kenaf fiber and tapioca starch.     

The Properties of Woven Kenaf and Betel Palm (Areca catechu) Reinforced Unsaturated Polyester Composites

The use of woven betel palm and kenaf lignocellulosic fibers as a reinforcing phase in unsaturated polyester was reported. The morphology, physical properties, and mechanical properties of the natural fibers and resulting woven composites were evaluated. Kenaf fibers exhibit higher tensile properties than betel palm fibers due to the higher amount of cellulose content. From the morphology observation, it is found that the alkaline treatment of the fibers effectively clean the fiber surface and increase the fiber surface roughness. Comparison between treated and untreated woven betel palm and kenaf composites at 7 vol% of fiber content was carried out. Interestingly, untreated woven kenaf composites exhibit comparable flexural strength with those of untreated woven betel palm composites. However, untreated kenaf composites exhibit superior flexural modulus to those of betel palm composites. In general, mechanical properties of the woven composites made from alkali-treated fibers were superior to the untreated fibers.     

Effect on Mechanical Performance of UHMWPE/HDPE-Blend Reinforced with Kenaf,Basalt and Hybrid Kenaf/Basalt Fiber

The aim of this study was to investigate the performance of UHMWPE/HDPE-reinforced kenaf, basalt and hybrid kenaf/basalt composites. Mechanical testing of these samples was carried out such as tensile, flexural (three-point bending) and an impact test (Charpy). Pure resin (UHMWPE/HDPE) samples were tested and compare with reinforced 10% weight fraction of kenaf, basalt and hybrid kenaf/basalt samples to identifying their contribution and potential in this new composite material. UHMWPE/ HDPE sample was produced in constant ratio 60:40 respectively via extrusion process. Basalt reinforced UHMWPE/HDPE generates the highest elastic modulus result compared to kenaf and hybrid kenaf/basalt as a reinforcement material. The tensile results of kenaf reinforcement UHMWPE/HDPE samples are significantly higher (20%) than pure blend resin, which is an indication for good performance of kenaf, basalt and hybrid kenaf/basalt to be used in UHMWPE/HDPE-blend polymers. The flexural and Charpy strengths show the drawback results, where performance of polymer is reduced 5% with the absence of kenaf. It can be concluded that kenaf, basalt and hybrid kenaf/basalt fiber successfully increase the UHMWPE/HDPE blends performance especially under tensile loading.     

Effect of operating parameters and chemical treatment on the tribological performance of natural fiber composites: A review

The demand for high-performance engineering products made from natural resources is increasing because of the low-cost, low-density, biodegradability, renewable nature and lighter than synthetic fibers. With these characteristics, the tribological performance of natural fiber composite has become an important element to be considered in most industrial and manufacturing functions. This paper presents an overview of the factors that influence the tribological performance of natural fiber composites, which include applied load, sliding distance, sliding velocity and fiber orientation. Influences of chemical treatment is also reviewed and illustrated through scanning electron microscope (SEM) observations. This review will focus on kenaf fibers (KFs) and oil palm fibers (OPFs) which have been widely exploited over the past few years among the available natural resources. The results show that the operating parameter, fiber orientation and chemical treatment has significant effects on the tribological performance of natural composite. A clear understanding of the factors that affect the tribological performance is very essential in performance improvement on natural fibers reinforced polymer composite for potential applications.