Material that can be used to adhere or stick one surface to another is called as an adhesive.What is a sealant?
Material that is initially fluid or semi fluid placed between two opposing solid materials, becomes solid by itself (by solvent evaporation or chemical reaction), bonds to the surface it is applied to and accommodates joint movement. Prevents excessive absorption of adhesives or penetration of liquid or gaseous substance.Whether excess adhesives is recommended to get better results ?
No.Whether surface preparation is important before applying adhesives ?
The basic ingredient in anaerobic adhesives is a acrylic or metha acrylic monomer. In the presence of free radicals initiated by hydroperoxide decomposition the monomer is becoming very reactive (Free radical form). This free radical monomer has an affinity for carbon but prefers to react with oxygen. As this monomer free radical reacts with oxygen molecules it forms a suitable liquid like an organic monomer.
If no oxygen is present the free radical then reacts with the carbon of the double bonded atom of the monomer molecule. Presence of metals speeds the polymerization process by causing production of free radical catalyst to increase greatly. The increased amount of catalyst in the monomer causes polymerization to occur more quickly. This anerobic reaction has been stated in a fairly simple manner, but it is really a very complex chemical reaction using certain ingredients in a parts per million basis.
Addition of multifunctional acrylate (like poly ethyleneglycol dimethaacrylate) will allow formation of thermo set product.Can Retaining compound used in place of Thread locker ?
Yes, However check the substrate surface finish and gap filling ability of the retaining compound before use.Why anaerobic grades are only half filled ?
Oxygen present in air behaves like an inhibitor preventing the polymirization of monomers and hence anerobic grades are only half filled.Is primer required before application of Anaerobic adhesives ?
No, anaerobic adhesives does not require primer for both active or passive metals.Whether anaerobic adhesives work in oily surfaces. If not why ?
Only fast curing anaerobic adhesive will work in oily surfaces. For slow curing anaerobic adhesives the presence of oil may reduce strength properties.How do we select anaerobic grades ?
Anaerobic grades are selected based on the below criteria
Anabond manufactures two types of coatings - Decorative (aesthetic) and Protective (anticorrosion) coatings.What is glossiness?
Gloss is an optical property of a surface to reflect light (mirror-like) with a smooth surface.What is pinhole in surface coatings?
Pinhole is one of the most common surface issue especially in sprayed application. It is a small sunken area that forms on a coating film after a bubble ruptures. Pinholes are one of the most common surface issue especially in sprayed application and after application the presence of pinhole / porosity is indication of the possibility of premature corrosion of the substrate.What are Plastic coatings?
Coating application of a thermoplastic to the surface of metal items to prevent corrosion and provide impact and chemical resistance.What are the advantages of water based coatings?
Water based coatings have water as the medium instead of solvent and water is Enviromental friendly.What are application solids?
Application solids are solid material which will remain with substrate after evaporation of solvents and it determines the coating thickness.What are the different types of coatings?
Based on polymers coatings are classified as polyurethane, epoxy, acrylic, UV, phenolic, polyimide, polyurea and alkyd coatings.
Yes, available.Whether Cyanoacrylate adhesives are brittle in nature?
Yes, unmodified cyanoacrylate adhesives are brittle in nature.What are all the steps to be taken, if the Cyanoacrylate adhesives contact with skin?
Cyanoacrylates on contact with skin immediately undergoes polymerisation. The polymerized product can be removed by repeated wiping with a piece of cloth wet with acetone or methyl ethyl ketone (MEK). In case, fingers are bonded by mistake, immediately dip the bonded finger in hot water (60 - 65º C) and apply a shear load to seperate the bonded fingers.What are all the precautions should take before opening of Cyanoacrylate adhesive bottles?
Do not shake the bottle of cyanoacrylate as this may induce the product to vaporize and build up ressure while opening. Beware of spillage while opening the bottle as the adhesive bonds skin. Keep away from eyes and wear protective gear while handling Cyanoacrylates. Open the bottle/tube gently to avoid breakage and spillage at the neck as the cap may get bonded to the tip if stored with out cleaning the nozzle.What is the meaning of Fogging?
The vapour of cyanoacrylate monomer reacts with the atmospheric moisture depositing a white powder on the surface of the bonded area. This is know as fogging.
Not always. Change of Mix ratio may affect the product performance drastically.What is the difference between a liquid epoxy and an epoxy putty?
Epoxy putties are non-sag in nature and hence do not sag while liquid epoxies are of lower viscosity and take the shape of the confining space.What adhesive is best to mend a broken vase?
For instant bonding , use Cyaboacrylate. Two component epoxies also will work well.What is an epoxy adhesive?
Epoxy adhesives are characteised by the presence of epoxy group capable of undergoing chemical reaction with active hydrogen containg compounds such as amines, acids, alcohol, phenol, thiol, etc. either at room temperature or at elevated temperature forming a completely cross linked three dimensional network structure. These epoxies can also undergo chemical reaction with acid andhydrides in the presence of catalysts.Q. What is the storage conditions for Epoxy products ? How it affect the product characteristics?
Anabond epoxies are available in one or two component systems. For single component system, the recommended storage temperature is below 5º C (41 ºF), away from direct sunglight and heat source. For two component systems, the storage temperature is at 20 to 35 ºC, away from direct sunlight and heat source.
It is an environmental friendly polymer as it does not contain silicone and isocyanate content.What is the advantage of MS sealant over Polyurethane sealant?
MS sealants have better adhesion, less sensitivity to moisture, better in low temperature application and it has higher mechanical stability and lower Tg (Glass transition termperature).What are MS sealants / polymers?
MS Polymer is silyl terminated polyether based sealant and it has a combination of silicone and polyurethane properties.
For porus substrate like concrete, primer is required to anchor the sealant well with the substrate / concrete.Is polysulphide a high modulus sealant?
No, it is low modulus sealant with lower mechanical strength.What is the purpose of using movement accommodation factor (MAF) for joint sealant?
MAF is defined as the total movemnt that a joint sealant can tolerate and is usually expressed as a percentage of the minimum design joint width. Failure to comply with this requirement results in overstressing the joint sealant.What is a Polysulphide sealant?
Polysulfides are sulfur-containing liquid polymers, which has excellent resistance to jet fuel, higher elongation and ultraviolet (UV) and ozone resistance.
In general in polyurethane, CASE means Coatings, Adhesive, Sealant and Elastomeric system and non-CASE systems are PU rigid foam & flexible foam.Are polyurethane adhesives better than silicone?
Polyurethane have better adhesion and are paintable but has lower thermal resistance than silicones.Does polyurethane exhibit good electrical property?
Polyurethane are excellent electrical insulators.
Yes.Tack free time means.
Tack-free time is the time taken to reach the point of losing the immediate stickyness.Whether Non-curing tape will be re-usable?
Yes. It is re-usable.How solvent based adhesives works?
In solvent-based adhesive product, solvent evaporates leaving the polymeric film which is responsible for holding the substrates.
Silicone sealant possess excellent thermal resistant and weather or UV resistant than polyurethane sealant.Can I paint over silicone?
NoWhat is meant by pot life?
Potlife is the length of time an adhesive remains usable (After mixing) for end use application.What is meant by . orm-in-place (FIP) gasket?
FIP gasket or liquid gaskets, are gaskets which is in pastte from, once th esealnt is dispensed onto one surface and assembeled onfto the mating part while the sealnt is still wet. After a sufficient cure period, the gasket joint relies on the adhesion of the material to both parts of the assembly to seal.Which type of condensation type one part RTV silicone sealant best suitable for potting application?
Deacetonation or Alkoxy cure type are best suitable for potting application since the by-products generated are neutral.What are the by-products of addition cure system?
No by-products generated by addition cure system.Is it possible to accelerate cure time of one part RTV silicone sealant in higher temperature.
If the cure mechanism is condensation type the curing rate does not accelerates with heat, since it depends on the moisture or humidity present in the atmosphere. Whereas if the cure mechanism is addition type, then the curing rate is accelerate with temperature.What are the by-products of condensation cure RTV silicone products?
Based on the nature of cure the by-products differs
Nature of cure By-products
Oxime cure Methyl ethyl ketoxime
Acetoxy cure Acetic acid
Alkoxy cure Respective alcohol
Amine cure AmineWhat are the different types of one part condensation cure RTV silicone products?
Based on the nature of cross linker used for curing mechanism, the one part condenstaion cure RTV silicone are broadly classified as:
a) Oxime cure
b) Acetoxy cure
c) Alkoxy cure
d) Amine cure
e) Amido cure and
f) DeacetonationWhat is meant by RTV?
RTV stands for Room Temperature vulcanization. The tendency of an RTV adhesive is to undergo curing or vulcanization at room temperature. The physical change is from a liquid or paste consistency into a rubber like consistency.