Phenolic resins are synthetic resins produced by the condensation of phenol or substituted phenol with an aldehyde like formaldehyde. There are two main types - novolacs and resols. Novolacs are produced under acidic conditions and resols under basic conditions. Phenolic resins have good electrical insulation properties and can retain properties at low temperatures. They are used in applications like circuit boards, radio cabinets, engine ignition equipment, cameras, and aerospace components.

1. PHENOLIC RESINS
MUHAMMED MUSTHAFA C.P
6TH SEM , DEPT. OF PS&RT
CUSAT

2. Contents
History
Introduction
Manufacture
Properties
Application

3. History
 1872 German chemist Adolf von Baeyer reported
reaction between phenol and aldehyde
 Synthesized by Leo Hendrik Baekeland in 1907
 1910 oil-soluble modified phenolic resins produced
by beherends
 1911 Bakelite company came under operations

4. Introduction
 The phenolic resins may be considered to be
the first polymeric products produced
commercially from simple compounds of low
molecular weight, they were the first truly
synthetic resins to be exploited.

5.  Phenolic resins are also widely known as
phenol-formaldehyde resins, PF resins and
phenoplasts.
 The trade name Bakelite has in the past been
ideally used

6.  The phenolics are resinous materials produced
by condensation of a phenol, or mixture of
phenols, with an aldehyde
Manufacture

7. RAW MATERIALS :- a) Phenol
b) Aldehyde
HCHO

8. TWO TYPES
NOVOLAK
 Prepared by reacting phenol
with formaldehyde in a molar
ratio of approximately (1 :0.8)
under acidic conditions.
 Slow formation
 Fast condensation
 Two stage resin
 Absence of active methylol
group
RESOL
 Produced by reacting a phenol with
an excess of aldehyde in a molar
ratio of (1.5-2:1) under basic
conditions
 Rapid formations
 Slow condensation
 One stage resin
 Presents of methylol group

9. RESIN MANUFACTURE
 In the manufacture of novolaks, 1 mole of phenol
is reacted with about 0.8 mole of formaldehyde
(added as 37% w/w formalin) in the presence of
some acid as catalyst. A typical charge ratio would
be:
PHENOL 100 PARTS BY WEIGHT
FORMALIN 75 PARTS BY WEIGHT
OXALIC ACID 1.5 PARTS BY WEIGHT

10. Resin kettle

11.  The reaction mixture is heated and allowed to
reflux, under atmospheric pressure at about 100°C.
At this stage valve A is open and valve B is closed.
 Because the reaction is strongly exothermic
initially it may be necessary to use cooling water in
the jacket at this stage.

12.  The condensation reaction will take a number of hours eg:
2-4hrs. since under the acidic conditions the formation of
phenol-alcohols is rather slow.
 When the resin separates from the aqueous phase and the
resin reaches the requisite degree of condensation, as
indicated by the refractive index measurements,
 Then the valves are changed over (ie. valve A is closed and
valve B opened) and water present is distilled off.

13. Properties
 Available as solids and solutions
 Solubility depends on the structure of the solution
 Decomposition temperature range is 120-250˚c
 Electrically insulating
 Good dimensional ability on heating
 Poor conductor of heat
 Retain properties at freezing temperature

14. Applications
 Phenolic resins are mainly used in the circuit board
production that is for making circuit board like PCB
….etc

15.  Radio cabinet

16.  Engine ignition equipment

17.  Camera

18.  Aerospace
application
FIBRE REINFORCED PLASTICS

19. REFERENCE
 J.A BRYDSON (1999) PLASTIC MATERIAL (7TH EDITION)
 WIKIPEDIA

20. THANK YOU