Wood/natural rubber composite

H. Ismail, H.D. Rozman, R.M. Jaffri, and Z.A. Ishak, Oil palm wood flour reinforced epoxidized natural rubber composites The effect of filler content and size. Eur. Polym. J. 33(10), 1627-1632 (1997). 

H. Ismail, and R. Jaffri, Physico-mechanical properties of oil palm wood flour filled natural rubber composites. Polym. Test. 18(5), 381-388 (1999). 

Non-metallic Materials Carbides, carbon, ceramic fiber, ceramic, cermet, composite, cork, elastomer, felt, fiber, glass, glycerin, non-metallic bearing material, rubber (natural), rubber (synthetic), silicone, wood, leather. 

It is almost paradoxical that in the history of mankind composite materials were earlier used than their "homogeneous" rivals. The earliest "engineering materials" were bone, wood and clay. Wood is a composite of matrix lignin and a cellulosic reinforcement bone is a natural composite where fibres of hydroxyapatite reinforce the collagen matrix and the oldest building material was adobe clay as a matrix, reinforced by vegetable fibres. After the industrial revolution other composites were added reinforced rubber, reinforced concrete, reinforced asphalt, etc. 

The usefulness of analytical pyrolysis in polymer characterization, identification, or quantitation has long been demonstrated. The first application of analytical pyrolysis can be considered the discovery in 1860 of the structure of natural rubber as being polyisoprene [10]. This was done by the identification of isoprene as the main pyrolysis product of rubber. Natural organic polymers and their composite materials such as wood, peat, soils, bacteria, animal cells, etc. are good candidates for analysis using a pyrolytic step. 

Lead, wood, and rubber are probably the earliest known materials of construction for the chemical processing industry. Interestingly, it took a little more than a century for rubber to be established as a lining material after Charles Goodyear accidentally discovered vulcanized rubber in 1839. Wood is the first composite material to be used in the chemical processing industry. Until the onset of World War II, these naturally occurring materials continued to play a major role in chemical handling applications. 

It is difficult to make a distinct classification of biodegradable polymers. Many authors have classified them according to their origin as natural or synthetic polymers. Both of these are subdivided into different classes based on the main linkages present in their structure. Thus completely biodegradable natural polymer subclasses include polysaccharides, polypeptides, polyesters, lipids, natural rubber and natural composites (wood). Partially biodegradable synthetic polymer subclasses include polyesters, polyur eas, polyurethanes, polyamides, poly( vinyl alcohol) and poly (ethylene glycol). 

Similar result were obtained when the oil palm wood flour (OPWF) was mixed with epoxidized natural rubber (ENR). The increase of OPWF content resulted in the decrease of tensile strength and elongation at break of the OPWF/ENR composites. However, it increased tensile modulus, tear strength and hardness. Moreover, the cure (t ) and scorch time decreased when the OPWF content increased. Larger particle size of OPWF resulted in shorter t and scorch time, while the highest fiber content with the smallest particle size resulted in the highest torque [27]. 

The objects of study were selected mixture of low-density polyethylene (LDPE) with wood flour (WF), natural rubber (NR) and ethylene-propylene rubber (EPDM). WF content is 40 wt.%. Rubber injected at 10 and 20 masses %. As composite materials based on LDPE blending performed on a laboratory mixer at a temperature of 140°C for 5 minutes and then get the film samples in a laboratory press. The sample thickness was 100 10 microns. 

NR (natural rubber) / neat pine wood flour composite (70%/30%) [6] ... 

Macromolecules, composed of thousands of atoms, are the basic components of the living world. Polymer macromolecules are part of a large number of materials used by man since the prehistory, such as leather, natural fibers (linen, cotton, wool, silk), wood and rubber. Their number has increased significantly in recent years. A large number of new polymers and composites were obtained. The common characteristic of chemical structure of polymers is the maciomolecule, which usually is a long chain, made of hundreds or thousands of mers, connected together by chemical bonds. The polymer chain ability to take different geometrical forms provides properties unattainable in the case of substances made of smaller molecules. 

Most of all, in daily life, shelter, clothing, food, education, and recreation depended, and still depend, essentially on the use of natural polymers—wood, cotton, fur, wool, silk, starch, leather, paper, rubber, and a variety of resins, glues, and coatings. Around each of these materials a highly sophisticated art developed—entirely empirical and without any basic knowledge and, in fact, in most cases, without any concern about the material s composition and structure. 

Natural fibres possess sufficient strength and stiffiiess but are difficult to use in load bearing applications by themselves because of their fibrous structure. Most plastics themselves are not suitable for load bearing applications due to their lack of sufficient strength, stiffness and dimensional stability [51]. In natural fibre reinforced composites, the fibres serve as reinforcement by giving strength and stiffness to the structure while the plastic matrix serve as the adhesive to hold the fibres in place so that suitable structural components can be made. The matrix for the natural fibres includes thermosets, thermoplastics and mbber. Different plant fibres and wood fibres are fotmd to be interesting reinforcements for rubber, thermoplastics and thermosets [52-58]. 

Currently the world s consumption of plastics is growing in this regard there are difficulties in disposing of large amounts of household plastic waste. The solution is to develop biodegradable polymers with a specific expiration date. This work is dedicated to the creation of biodegradable composite material based on LDPE, wood flour and rubbers of different nature. 

The distinction between natural and synthetic pol5uners or PMC (eg, natural versus synthetic rubber, plastics versus biopolymers, wood versus fiber-reinforced composites) is of limited relevance for the application of NDT methods. 

Basically a polymer composite contains a polymer and a nonpolymer. While polymer composites include such compositions as foams and some types of gels, this chapter will be restricted to compositions of one or more polymers and one or more nonpolymers in the bulk state. There are a few points of overlap between blends and composites polymer-impregnated wood (where wood itself is a natural polymer blend), and organic fiber (e.g., polyester) reinforced plastics constitute examples. Compositions of special interest to this chapter include glass fiber reinforced plastics, carbon black reinforced rubber, and mineral-pigmented coatings. 

Section three contains six chapters dealing with the noncellu-losic components of plant life including tall oil, wood and gum rosins, lignan, bark extracts, tannin, wood flour, and rice hull flour for use in the preparation of composites, resins, adhesives, and fillers. Filler properties are described in some detail. Substitutes for phenol-formaldehyde resins are described as well as the generation of the industrially important trimellitic anhydride from natural sources. A problem in the rubber elasticity of gutta percha networks is discussed. 

---