What are novolac in polymers?

Novolaks (sometimes: novolacs) are low molecular weight polymers derived from phenols and formaldehyde. They are related to Bakelite, which is more highly crosslinked.

What is the difference between novolac and Bakelite?

1 Answers. :linear stucture formed as a product of condensation reaction between phenol and formaldehyde with excess of phenol. Bakelite: :Novolac on further heating with formaldehyde undergoes cross linking to form an infusible solid mass called bakelite.

Is novolac a thermoplastic?

Novolacs resemble the polymer except that they are of much lower molecular weight and are still thermoplastic. Curing to network polymer is accomplished by the addition of more formaldehyde or, more commonly, of compounds that decompose to formaldehyde on heating.

What is the difference between resole and novolac?

Differences Between Resole and Novolac Phenolic Resins 1. Resole phenolic resins are produced by using alkaline catalysts, whereas novolac resins are produced via acidic catalysts. 2. Resole phenolic resins are produced via B-staging while novolac resins are made by pre-polymerization.

What is epoxy novolac resin?

Epoxy Novolac Resins. EPON 1031. EPON™ Resin 1031 is a solid, novolac-free multifunctional epoxy resin. It is most frequently used to improve the properties of cured epoxy resin systems particularly at elevated temperatures.

How is novolac resin prepared?

Novolac is one of the phenolic resins made under acidic conditions using excess phenol, the acid catalyzes the reaction of phenol and formaldehyde to form the cross-linkable polymeric resin. It is widely used for the formation of molded pieces and articles [1].

What is the use of novolac?

What Does Novolacs Mean? These are resins produced by the complete poly-condensation of phenol and aldehydes for industrial uses as a replacement of natural resin such as shellac. They are available in solid and liquid form and is used in binders, articles, paints, molded pieces, laminated plastics and adhesives.

What is the structure of novolac?

Novolacs are phenol–formaldehyde resins with a formaldehyde-to- phenol molar ratio of less than one and are prepolymers for cured phenolic resins. Polymerization is completed using acid catalysts such as oxalic, hydrochloric or sulfonic acids.

What is a novolac epoxy?

Five Star® Epoxy Novolac Coating is a two-component, 100% solids, highly chemical resistant epoxy coating for horizontal and vertical applications effective on both steel and concrete.

Is novolac a polyester?

Answer is (1) Novolac Novalac is a linear polymer of [Ph–OH + HCHO]. So ester linkage not present. So novalac is not a polyester.

What is novolac epoxy?

How epoxy novolac are made?

Novolacs are produced by reacting phenols with formaldehyde (methanal). These are highly functional resins, which carries around 2 to 6 epoxy groups per molecule, and results in a highly cross-linked polymer upon curing.