resin composite material

Bakelite is made from phenol and formaldehyde in the presence of a base catalyst. It involves formation of methylene bridges at the ortho and para positions. The reaction starts with the initial formation of ortho and/or para-hydroxymethyl phenol derivatives which further react with phenol to form ..

As an industrial solvent for fats and oils, rubber, resins etc. As a starting material for dyes, drugs, perfumes and explosives and polymers For dry-cleaning of woollen clothes. As a motor fuel along with petrol, under the name benzol..

A quick count of industries based on forest produce reveals timber, paper, resin and gum, lac, natural oils, minor foods products, medicines, sports equipment. Industries consider the forest as merely a source of raw material for their factories. They neither are interested in..

Introduction - The nitrogenous waste materials produced in the animal body due to metabolic reactions are of no use to the cell. These waste materials if allowed to accumulate in the body, may become toxic. Therefore, they must be removed from the body. The process of eliminatio..

The nitrogenous waste materials produced in the animal body due to metabolic reactions are of no use to the cell. These waste materials if allowed to accumulate in the body, may become toxic. Therefore, they must be removed from the body. The process of elimination of meta..

Neoprene is superior to natural rubber because of the following properties: Neoprene is non-inflammable but natural rubber is inflammable Neoprene is resistant to oils, organic solvents, petrol and grease. Natural rubber swells and rots in contact with these materials Neoprene is..

In plants, breakdown of substances is much slower than in animals. Hence accumulation of waste is much slower and there are no special organs of excretion. Green plants in darkness or plants that do not contain chlorophyll produce carbon dioxide and water as respiratory waste products. Carbon diox..

Impure Substances - Mixtures Impure substances are commonly called mixtures. A mixture is a material containing two or more elements or compounds that are in close contact and are mixed in any proportion. The constituents of mixtures exhibit their individual properties. These constitu..

Question: What direct value does a forest have for man? Answer: Forests contribute to the economic development of our country by providing goods and services to the people and industry. They are intimately linked with our culture and civilization. Forests are useful to us for the follow..

Pollutants are ingredients causing pollution. They may be gases, liquids, solids of different chemical composition or may be high pitched sounds. The pollutants are not deliberately manufactured. But they are the by products of manufacturing processes. At different stage of manufacturing,..