Thermal Initiation of Radical Polymerisation and Related Concepts

These flashcards cover key concepts related to the thermal initiation of radical polymerisation and its associated processes, including initiation, propagation, termination, and regiospecificity.

Homolytic cleavage t½ at 100 ºC is __.

7.2 mins

Azoisobutyronitrile is also known as __.

2,2'-(diazene-1,2-diyl)bis(2-methylpropanenitrile)

Photoinitiators are used in __ processes.

Photochemical initiation.

In radical polymerisation, typically 100 – __ propagation steps occur per initiation step.

1000

Radical chain end stabilization is influenced by __, steric and resonance effects.

polar

The typical regiochemistry in radical polymerisation shows __ chain growth with less than 2% H-H or T-T placements.

head-to-tail

At -20°C, the percentage of 1,2-linkages is __% regardless of temperature.

20

Steric effects from b-carbon lead to preference for __ placements in radical polymerisation.

syndiotactic

Termination in radical polymerisation can occur by __ or disproportionation.

Combination

Chain transfer can lead to __ and may lead to crosslinking in radical polymerisation.

chain branching

The general mechanism of radical polymerisation includes initiation, transfer, and __.

termination

Transfer to polymer during polymerisation can result in __ chain branches.

short