Brief introduction of the various Adhesives
1) Anaerobic polyster Adhesive :-Introduction -This adhesive remains liquid in the presense of air but cures quickly without air, hence it is called anaerobic adhesive.
Properties - This adhesive is non-toxic, has a storage life of more than 1 year, it is soluble in TCE and other organic solvents while being insoluble in oils, water,gasoline,Freon etc.
Uses - It is used for bonding and sealing purpose. Screws,bolts,studs etc. may be made loose proof by it, and can be used for gap filling of inserted parts of machines such as bearings.
2) Asphalt Adhesives :-
Introduction - Asphalt or bitumen based adhesive are usually black in colour, and are in the form of water emulsions,hot melts or solvent solutions. Brown asphalt gives better weatherability and impact resistance.
Properties - They have poor strength and depending on formulation may be soft, sticky or hard. They are resistance to the water,acid,alkalies but not oils and solvents.
Uses - Asphalt or bitumen adhesive are widely used as plastic flooring adhesive. They are used for the concrete, glass, metal, felt, paper lamination bonding and in corkboard insulation.
3) Blood albumen Adhesive :
Introduction- Dried blood albumen is a light brown powder which is mixed with water,lime or sodium hydroxide. It sets rapidly at 80 C by loss of water and coagulation of blood.
Properties - It is good resistance to boiling water but is attacked by bacteria, fungus and insects. Ageing properties are moderate,and are suitable for interior use only.
Uses - blood albumen adhesives are used for interior grade polywood manufacturer, and for bonding of porous materials such as cork,leather,textiles,papers.
4) Butadiene-vinyl pyridine Adhesive
Introduction-Butadiene-vinyl pyridine adhesives are prepared by the copolymerization of the butadiene and vinyl pyridine or butadiene styrene vinyl pyridine.
Properties-They give strong adhesion on a highly polar material. These adhesives are used for the adhesion of nylon tyre cord in cojuction with an aqueous solution of resorcinol-formaldehyde resin.
Uses-These adhesives are used for adhesion of the nylon tyre cord in a conjuction with an aquous solution of resorcinol-formaldehyde resin.
5) Butyl rubber and polyisobutylene Adhesive
Introduction-These are thermoplastic elastomers Polyisobutylene is a homopolymer while butyl rubber is a copolymer of isobutylene and isoprene. They are used in the form of liquids and mastics using naptha.
Properties-They have good resistance to ageing. Mineral oils,acids,ozone,water etc. They have low permeability to gases,vapour,moisture.
Uses-These adhesives are not quite popular. They are used as adhesives for polyethelene and cellophane. They may be used for paper and stationary.
6) Carboxy Methyl cellulose Adhesive
Introduction - Carboxy methyl cellulose or CMC has a structure similar to that of sodium alginate but differs in shearing thioxytropy.
Properties-It is a colourless,odourless and nontoxic white powder. The product having substitution degrees of more than 0.6 dissolve completely in water forming viscous pastes.
Uses-It is as a paste for printing,finishing,washing of textiles and as sizing agent for paper. CMC based adhesive may be used for bonding paper to wood.
7) Casein Adhesive
Introduction - Casein is a protein obtained from the milk by acid coagulation or rennet process. Its shelf life at 20c is 1 year and working life about 12 hours.
Properties - Casein adhesives are not suitable for the outdoor use though more resistant to temperature change and moisture than other water based adhesives. Resistance to the dry heat upto 70c is good.
Uses - Casein adhesive are used for woodwork,furniture and interior grade plywood fabrication. Casein-latex adhesive are used for bonding of wood to metal paneling,laminated plastics to wood and metal and linoleum to wood.
8) Cellulose acetate Adhesive
Introduction - These adhesives are available as solids of hot-melt type, solvent solutions in esters,ketones or chlorinated hydrocarbons.
Properties - Cellulose acetatevis less inflammable than cellulose nitrate. Also it is less water resistat,but has better colour and heat resistance, the maximum service temperature being 50c.
Uses-These adhesives are used for cellulose acetate plastics and photographic films and porous materials like leather,paper and textiles etc.
9) Cellulose acetate-Butyrate Adhesive
Introduction-These area available in various forms like cellulose-acetate. They also have cold flow but adhesion to rebber,metal and glass is better.
Properties-They have better water resistance and heat stability,excellent resistance to biodegradation but cannot withstand long immersions in organic solvents.
Uses-They are used for heat sealing of porous and semiporous materials based on papers,textiles,wood and leather etc.
Introduction - Carboxy methyl cellulose or CMC has a structure similar to that of sodium alginate but differs in shearing thioxytropy.
Properties-It is a colourless,odourless and nontoxic white powder. The product having substitution degrees of more than 0.6 dissolve completely in water forming viscous pastes.
Uses-It is as a paste for printing,finishing,washing of textiles and as sizing agent for paper. CMC based adhesive may be used for bonding paper to wood.
7) Casein Adhesive
Introduction - Casein is a protein obtained from the milk by acid coagulation or rennet process. Its shelf life at 20c is 1 year and working life about 12 hours.
Properties - Casein adhesives are not suitable for the outdoor use though more resistant to temperature change and moisture than other water based adhesives. Resistance to the dry heat upto 70c is good.
Uses - Casein adhesive are used for woodwork,furniture and interior grade plywood fabrication. Casein-latex adhesive are used for bonding of wood to metal paneling,laminated plastics to wood and metal and linoleum to wood.
8) Cellulose acetate Adhesive
Introduction - These adhesives are available as solids of hot-melt type, solvent solutions in esters,ketones or chlorinated hydrocarbons.
Properties - Cellulose acetatevis less inflammable than cellulose nitrate. Also it is less water resistat,but has better colour and heat resistance, the maximum service temperature being 50c.
Uses-These adhesives are used for cellulose acetate plastics and photographic films and porous materials like leather,paper and textiles etc.
9) Cellulose acetate-Butyrate Adhesive
Introduction-These area available in various forms like cellulose-acetate. They also have cold flow but adhesion to rebber,metal and glass is better.
Properties-They have better water resistance and heat stability,excellent resistance to biodegradation but cannot withstand long immersions in organic solvents.
Uses-They are used for heat sealing of porous and semiporous materials based on papers,textiles,wood and leather etc.
