PolyIsoButylene

1. POLYISOBUTYLENE
Polymer Synthesis
By: Kudzai Hamish Ruzvidzo
B Tech (Chemical Process Systems Engineering)
M Tech (Polymer Science and Technology)
vakudzaihamish@gmail.com

2. Introduction
• Polyisobutylene is a synthetic rubber, or elastomer
• It's special because it's the only rubber that's gas impermeable, that is, it's
the only rubber that can hold air for long periods of time
• Because polyisobutylene will hold air, it is used to make things like the
inner liner of tyres, and the inner liners of basketballs.
• . Polyisobutylene is a colorless to light yellow viscoelastic material. It is
generally odorless and tasteless, though it may exhibit a slight
characteristic odor.
• Polyisobutylene was first developed by the BASF unit of IG Farben in 1931
using a boron trifluoride catalyst at low temperatures and sold under the
trade name Oppanol B

3. Monomer
• Polyisobutylene is a vinyl polymer made from the isobutylene monomer
• Polyisobutylene is very similar to polyethylene and polypropylene in
structure, except that every other carbon is substituted with two methyl
groups
• Isobutylene is a colorless gas with a faint petroleum-like odor

4. Synthesis
• PIB is made from the monomer isobutylene, by cationic vinyl
polymerization.

5. Polymerization
• The polymer is formed by a process called cationic vinyl polymerization and
is highly exothermic.
• It involved the use of an initiator or cation, which attracts a pair of
electrons from the carbon-carbon double bond, thus forming a single bond
with the initiator.
• One of the carbons, previously double bonded is now positively charged
and will react with another monomer, similarly to the initiator.
• The process is repeated the polymer is formed.
• The polymerization reaction is usually carried out at temperatures in the
range –100°C to control the reaction rate. At higher temperatures, the
reaction proceeds too fast to control.

6. Mechanism

9. Properties
• Air tight and gas impermeable
• Flexibility
• Good weathering resistance
• Resistant to ozone
• Good vibration damper
• Biocompatible

10. Uses
• the inner liner of tyres
• Inner tubes
• inner liners of basketballs, footballs e.t.c
• stoppers for medicine bottles and pharmaceuticals
• Sealants and adhesives
• O rings
• Joint replacements (biomedical)
• Chewing gum
• Tank and pond liners
• Speaker surrounds