Polyethylene (PE)

1.

Polyethylene (PE)
Types of Polymerization:
Free Radical Polymerization – Uses initiators (e.g., peroxides)
under high pressure and temperature. Produces low-density
polyethylene (LDPE).
Catalytic Polymerization – Uses catalysts for controlled polymer
growth. Produces high-density polyethylene (HDPE) and linear lowdensity polyethylene (LLDPE).

2.

Polypropylene (PP)
Types of Polymerization:
`
Ziegler-Natta Polymerization – Uses Ziegler-Natta catalysts
(TiCl4_44​ + AlR3_33​) for isotactic or syndiotactic polypropylene.
Metallocene Catalysis – Provides more precise control over polymer
structure.
Radical Polymerization – Less common due to challenges with
stereoregularity.

3.

Acrylics (PMMA) methyl
methacrylate
Polymerization Process:
PMMA is typically produced via radical polymerization, which
occurs in three main steps:
1)Initiation: A free radical initiator (e.g., benzoyl peroxide)
generates reactive species.
2)Propagation: Monomers continuously add to the growing
chain.
3)Termination: The polymer chains stop growing when radicals
combine.