Heat of polymerization
| material | kJ / mol |
|---|---|
| Styrene | -70 |
| Vinyl chloride | -71 |
| Vinyl acetate | -88 |
| Acrylonitrile | -79.4 |
| Acrylic acid methyl ester | -80 |
The heat of polymerization is in technology and chemistry a special form of reaction heat , which in chain polymerizations of a particular monomer occurs and a homopolymer results. After IUPAC the designations polymerization enthalpy (Δ H m , SI unit : J mol -1 ) or molar heat of polymerization is recommended.
Chain polymerizations are exothermic reactions , as the resulting polymers are lower in energy than the mostly unsaturated monomers .
In industrial processes, the considerable heat of polymerisation has to be dissipated by external cooling in order to prevent the polymerisation rate from increasing exponentially, which can lead to an explosion. (See Trommsdorff Effect .)
Remarks
- ↑ The word polymerization swärme relates generally only chain polymerizations, as in German-speaking often and not IUPAC -compliant with polymerization only polymer-forming reactions , which chain reactions are meant to run.
Individual evidence
- ↑ a b c d Trade Association Raw Materials and Chemical Industry , Leaflet R 008 Polyreactions and polymerizable systems. Edition 05/2015, ISBN 978-3-86825-069-5 . (.pdf)
- ↑ Brandrup, J .; Immergut, EH; Grulke, EA; Abe, A .; Bloch, DR: Polymer Handbook , 4th Edition, Wiley-VCH 2003, ISBN 978-0-471-47936-9 , p. II / 368.
- ↑ Ulrich Jonas, Patrick Theato: Glossary of terms related to kinetics, thermodynamics and mechanisms of polymerizations (IUPAC recommendations) , In: Angew. Chem. , 2009, Vol. 121, No. 50, pp. 9725-9738.
- ^ A b Karlheinz Biederbick: Kunststoffe , Vogel-Verlag, 4th edition, 1977, pp. 54–55, ISBN 3-8023-0010-6 .