Many will wonder how polymer relates with paints, or how polymers (plastics or nylon, which is their foremost knowledge of polymers) are used in the production of paints. Well, there is no need to wonder any longer because I’ve put together this piece to educate you on how paints are polymeric products.
What is PAINT? Paint is any substance that is applied as a liquid or paste and dries into a solid coating and decorates, protects and prolongs life of the object or surface to which it has been applied, and acts as a barrier against environmental conditions. Paints are used in every aspect of life both industrial (automobile, marine, pipeline coating etc.) and domestic (houses). Although, I will not be going in details to explain the various application or uses in these aspects.
Paints comprises four major components which are;
- Binder (resin) 30%
- Solvent 40%
- Pigments 25%
- Additives 5%
BINDER: this is also referred to as the resin and it is a polymer which forms a matrix to hold the other components of the paints together. It forms a film, serves as the non-volatile vehicle that carries the other components of the paints and it is non-hazardous. The binder contains not less than 30% of the paint’s composition. Examples of polymers that are used as binders in paint production are; acrylics, epoxy, alkyd, polyurethane, vinyl, linseed oil. Paints are named according to their binders, and I will briefly discuss the three most common binders which are; acrylics, alkyd and epoxy.
- Acrylics paints: these are the commonest paints and also the cheapest of them all. They are also the widely used paints because they are majorly for domestic purposes. Another name or acrylic paints is emulsion paint. They are mostly used for decorative and protective purposes such as painting the inside and outside of buildings. Specific polymers used in this are poly (vinyl acrylate), poly (vinyl alcohol), etc.
- Alkyd paints: these are commonly known as gloss or oil paints and they are more expensive than the acrylic paints. They are mostly used for metal coating, and can be used for both industrial and domestic purposes (as metals are used in both our homes and industries). Specific polymers used for this purpose are alkyd resin which is gotten from polyol (propane-1,2,3-triol glycerol), dibasic acid (benzene-1,2-dicarboxylic phthalic anhydride) and a drying oil (linseed or soya bean oil); another polymer used for oil paints is polyurethane.
- Epoxy paints: these are applied as sprays and varnishes. They are expensive and have high resistance to corrosion that is the reason they are used for specific purposes such as the painting an automobile, aircraft, ships, storage tanks etc. they are comprised of epoxides.
SOLVENT: this reduces the viscosity of the paint, keeps the paint liquid but evaporates on application. They are hazardous and it is the reason one needs to dispose paint remnants properly so as to avoid being a victim to this hazard. Chemicals such as kerosene, mineral spirit, toluene can be used as solvent in paint production.
PIGMENT: this provides colour and covering power to the paint. It also gives the opacity and helps in viscosity control. A typical example is azo-compounds.
ADDITIVES: these are chemicals that generally used as stabilizers, dryers, thickeners, preservatives, emulsifiers etc. during paint production. Examples are calcites, titanium dioxide and so on.
Surely it can be said that paints are polymer products and this piece has widened your knowledge about polymers and how useful they are to our environment.
I believe by now knowledge has been impacted to you or your memory refreshed as regards polymers and their products. Kindly do me a fovour by sharing this post on your facebook, twitter, google plus or better still post the link to your whatsapp contacts for them to come over here to benefit from this.