Material resources paper

There is growing interest in the use of cereal straws such as wheat straw for animal feed after increasing its digestibility by various methods, or as a raw material for paper and board production. This is particularly important in areas with limited forest resources (1). For all these purposes a good physicochemical characterisation of cereal straw is necessary. 

As with most commodity chemicals, the stoichiometric chemical costs remain the dominant component of overall process economics, but success in the marketplace depends critically upon the most efficient utilization of capital, energy, and raw material resources to gain and retain the economic upper hand. Programs like the one described in this paper are designed to do just that. 

Misra M, Park H, Mohanty A K, Drzal L T (2004), Injection molded green nanocomposite materials from renewable resources. Paper presented at GPEC-2004, Feb. 18-19. 

Paper (qv) is a material of tremendous versatility and utility, prepared from a renewable resource. It may be made soft or stiff, dense or porous, absorbent or water repellent, textured or smooth. Some of the versatility originates with the fibers, which may vary from short and supple to long and stiff, but the contribution of chemicals should not be underestimated (see Papermaking materials and additives). 

Seventy years ago, nearly all resources for the production of commodities and many technical products were materials derived from natural textiles. Textiles, ropes, canvas, and paper were made of local natural fibers, such as flax and hemp. Some of them are still used today. In 1908, the first composite materials were applied for the fabrication of big quantities of sheets, tubes, and pipes in electrotechnical usage (paper or cotton as reinforcement in sheets made of phenol- or melamine-formaldehyde resins). In 1896, for example, airplane seats and fuel tanks were made of natural fibers with a small content of polymeric binders [1]. 

Wood is one of the oldest constructional materials. Historically it was important in world exploration and trade, and the defence of that trade, in the provision of merchant ships and navies. It was also important in the early days of railway engineering and in building construction. Although in many applications wood has been replaced by other materials, this renewable resource now supports the growing industries of manufactured wood products. Prominent amongst these are the panel materials chipboard, flake-board, strandboard, plywood and blockboard, hardboard and softboard, wood-cement products and the products of the very large pulp and paper industries. 

One of the problems that face our civilization is the fact that the pressure on natural resources is reported to be hindering progress. Periodically an energy crisis exists that has led to a so-called materials crisis in plastics and even other materials such as cellulose papers. Petroleum is currently the major source of raw materials for most high volume plastics. 

In addition to the solid waste problem, we can also expect that with expanding population or expanding demands of a static population, there will be societal pressure to reduce material usage over and above cost factors. These pressures could result in legislation to expand the environmental protection philosophy. For example, since plant materials are a renewable resource as well as readily recyclable, we may expect forced increases in paper-based packages. 

Xylan-type polysaccharides are the main hemicellulose components of secondary cell walls constituting about 20-30% of the biomass of dicotyl plants (hardwoods and herbaceous plants). In some tissues of monocotyl plants (grasses and cereals) xylans occur up to 50% [6j. Xylans are thus available in huge and replenishable amoimts as by-products from forestry, the agriculture, wood, and pulp and paper industries. Nowadays, xylans of some seaweed represent a novel biopolymer resource [4j. The diversity and complexity of xylans suggest that many useful by-products can be potentially produced and, therefore, these polysaccharides are considered as possible biopolymer raw materials for various exploitations. As a renewable resource, xylans are... 

An Ecoprofile is an assessment of the environmental and resource impacts of a waste disposal process. This paper describes ecoprofiles for six different ways of disposing the plastic fraction in municipal solid waste -two material recycling processes that include separation of the plastic waste, material recycling without separation of the plastic waste, pyrolysis, incineration with heat recovery, and landfill. 17 refs. 

STARCH. Starches are used as components and/or processing aids in the production of resources such as aluminum, paper, copper, water, and oil. The use of this natural polymeric material is based on its... 

Recycling creates places of employment and saves the resources raw material, energy and water. Wood is a very important renewable raw material which is used in many fields of application. Also, the paper industry requires wood for the production of virgin fibres to ensure the multiple use of the construction material paper. It is necessary to upright the paper recycling loop to cover the tremendous demand of paper in Europe. 

Smith, K. J. ACS Symposium Renewable Resource Material for Coatings and Plastics, New York 1981. Ed. by L. Sperling and C. Carraher. In press. And two papers submitted to... 

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