SILICONES AND THEIR IMPORTANT INDUSTRIAL APPLICATIONS

   

1.  Introduction

Silicones are inorganic synthetic polymers with alternate silicon and oxygen atoms, having organic groups attached to silicon atom. The silicones was given that name due to their resemblance with ketones by kipping in 1901 having the brut formula R₂SiO. These are actually known as plydialkylsiloxanes having formula

  R

  I

(Si - O -) n

  I

  R

2.  Industrial applications of Silicones

The quality of life is protected and improved by silicone products. From aviation to textile, the quality of everything is enhanced by silicone and they makes the rout for new products. The important industrial applications of silicones are discussed below:

2.1.    Health Care

Silicone made medical infant care products and applications provides the highest quality standards to fulfil the demand of health care professionals, families and patients. They have resistant to bacteria and can be sterilized easily. They are inert and do not irritate the body.

Silicone tubing in various medical devices like drug delivery systems and heart pacemaker helps to minimize the risk of infections. Silicone boost lubricants facilitate the insertion of devices and needles. They can be used externally, intravenously or internally and not trigger allergic reactions and unwelcome by-products. Silicones help to soften and smooth medications that can be applied without having greasy residue and helpful in forming a seal for protecting the wounds during healing process.

Silicones can most likely approximate the uniformity of skin and offer extraordinary cushion and consolation in prosthetics.

2.2.        Aviation and Aerospace

Silicones are used in various aspects of spacecraft and aircraft assembly and maintenance due their extraordinary ability to withstand extreme stress and temperature conditions. Silicones are used as sealants and adhesives for protecting and sealing various elements such as windows, doors, hydraulic switches, fuel tanks, leading electrical devices and engine gaskets etc.

2.3.    Construction

Silicone sealants, coatings and adhesives improves the working of construction materials and makes them to work last longer. Diverse materials can be bonded by silicone adhesives such as glass, concrete, steel, granite and plastics. This provides innovative engineering and architecture such as curved and suspended structures and dramatic glass facades. Silicone sealants make the material stay affixed and protects them from earth quake and movement from wind by absorbing stress.

2.4.    Electronics

Silicones have provide advancement in telecommunication, technology and macro and micro-electronics and electrical power distribution.

Highly sensitive materials such as circuits and microprocessors to semiconductors are protected by sealing and bonding them. They provide protection to electronic equipments from moisture, heat, salt, corrosion, and movements in appliances, cars, and airplanes. Silicones provide electronic and technological innovations.

2.5.    Household Products

The cookware and bakeware which are made of silicone rubber are more convenient, sturdy, long lasting and easy to use. The non-stick and flexible surface is facile to clean and does not drift any odour or flavour to food. The baking mats, muffin molds and cake pans made of silicone do not affect the quality of food product.

The household polishes and cleaners made of silicone are ideal for countertops and floors. They increase the shine, their spreading is facile and have no chemical reaction with surface materials.

Silicones are used in fabric softeners to preserve the “newness” due to their softening properties. They are also used as anti-foaming agents in detergents.

2.6.    Paints and Coatings

With the advancement in silicone technology, exterior coatings and paints have become last longer and can stand up to salts, pollution, sun and age better than ever. The silicone paints provide extraordinary adhesion, stain, chemical and weather resistance and better chemical dispersion. Advance silicone based paints help to keep the exterior coatings of bridges, houses and railway cars flexible so that they remain unaffected from freeze and thaw cycles chalking, blistering, cracking and peeling. Silicone coatings on oil-rig, highway and road surfaces remain unaffected from corrosion, acid rain and salt spray.

2.7.        Paper and Film

Silicones extraordinary foam controlling ability provides advancement in paper and pulp processing and make the production easier on larger scales. Silicones also have huge market as paper release agents. Silicones provide pressure sensitive adhesives. They are resistant to temperature and humidity and are good for using in extreme environments such as in hot engine compartments of a vehical or tapes that need to adhere to outer surface.

2.8.    Personal Care Products

Versatile silicones provide various exceptional qualities that are associated with personal care products, silky smoothness, luxuriant texture, luster and smooth applications.

The personal care products made of silicones are non-irritating and non-stinging. For example, silicones minimizes the tacky feel and white residue of antiperspirants in deodorants.

Silicones provide long lasting make-up and also retain its luster and colour. Hair conditioners and shampoos containing silicone have better shine and stronger SPF and have improved wetting and spreading qualities of sunscreens, lotions and cleansers

2.9.    Restoration

Silicones facile to restore historical buildings landmarks and buildings without changing the original integrity and appearance of the material. Sealants and adhesives made of silicones srengthen the “weatherability” and natural strength of the structure and joints. They are water repellent and allow "breathability" to natural materials eg. porous limestone and porous soapstone. Silicone coatings  have uniformity and do not have the risk of streaking or straining.

2.10. Sealants and Adhesives

Silicones are perfect for affixing materials and are utilized in construction, expansion, connection and for moving joints. Silicone rubber keeps the material in place and the joints are able to absorb the shifting and movement from temperature and humidity fluctuations and various other environmental factors.

In the home, sealants made of silicone rubber are used in kitchens and bathrooms to prevent damage from bacteria build-up and moisture.

Structural glazes made of silicone rubber secure the long term appearance of facade and quality. They can either be manufactured with material or can be applied on the finished surface and these industrial and commercial structure can withstand exposure to extreme conditions. Silicone rubber glazing protects and insulates glass panels in cars and facades from UV radiation.

2.11.Textiles and Leather

Silicones have dramatically alter the fabrics of all kind. They are used as finishes to retain the texture, shape and resistance to abrasion. They are used to achieve brilliance and uniformity of colour. They are used for water proofing the raingear and leather shoes and seal out goggles and diving masks from water.

Silicones enable new routes for designing sportswear having lightweight, water repellent, durable and high performing and also allows the fabric to maintain “breathability”.

Silicones maintain the colour and quality of dry-cleaned clothes because they are inert and do not interact with the fabric. Home fabric softeners made of silicones helps in preserving the textiles due to their softening properties and their elasticity also maintains the smooth wrinkles.

2.12.Rubber

From cake pans to keypads and from tubing to tires, silicone rubber is essential in various sophisticated synthetic and production processes.

The formulation and manufacturing of silicone rubber is easy and essentially applicable to most trades and accessible in varying hardness and colour. Silicone rubber has a variety of formulation for molding, curing and manufacturing, it facilitates business streamline their processing and ensures the consistent quality production. Silicone rubber when used with right technology, provides advance design opportunities and synthetic solutions.

Silicone rubber can be easily cured and molded to create materials, including electronic and automotive sealants and gaskets, cables, tires, food molds, industrial molds, artistic replications, play and toy equipment, molds, bakeware and reproduction.

2.13.Transportation

In high-performance automobiles, planes, ocean vessels spacecraft and planes, silicones give strength, durability and adhesion.

The service life of cars, boats and planes can be extended by using silicones coatings and adhesives. Exteriors become more resistant to wind, rain, abrasion, salt, chemicals and ultraviolet radiations. The joints coated with silicones are last longer and their maintenance and repair is less costly.

Silicones are now used in a wide range of car parts including: engine gaskets, headlamps, airbags, ignition cables, hydraulic bearings, radiator seals and shock absorbers, ventilation flaps and spark plug boots.

Silicone rubbers offers superior traction and long bear life to tires and silicone release coatings offer the tire manufacturers in getting the tires out of their manufacturing molds.