Polypropylene carbonate
5625381
223095596
2008-07-02T15:31:51Z
74.1.175.18
'''Polypropylene carbonate''' ('''PPC'''), also called '''poly(propylene carbonate)''', is a [[polyalkylene carbonate]] [[plastic]] material, a [[copolymer]] of [[carbon dioxide]] and [[propylene oxide]]. It is made by reacting the monomers in presence of eg. a [[zinc glutarate]] [[catalyst]]. Its [[CAS number]] is {{CASREF|CAS=50862-75-4}} or {{CASREF|CAS=25511-85-7}}.
Polypropylene carbonate is soluble in [[chemical polarity|polar]] [[solvent]]s, eg. [[acetone]], [[methyl ethyl ketone]], [[ethyl acetate]], [[dichloromethane]] and [[chlorinated hydrocarbon]]s. It is insoluble in [[ethyl alcohol]], [[ethylene glycol]]s, water, and [[aliphatic hydrocarbon]]s. Stable [[emulsion]]s in water are available commercially only from Empower Materials Inc., Newark DE USA. [http://www.empowermaterials.com]
Polypropylene carbonate is used eg. as a [[binder (material)|binder]], and to increase the toughness of some [[epoxy resin]]s. It is unsuitable as an oxygen barrier, and therefore is used in applications where diffusion of oxygen through the plastic is desired.
In ceramics industry, polypropylene carbonate and [[polyethylene carbonate]] are used as sacrificial [[binder (material)|binder]]s, especially [[alumina]] and [[silicon carbide]]; the polymers evaporate during [[sintering]] as they decompose completely above 300 °C. Together with [[plasticizer]]s they account for the most of the volumes of the ceramic additives; a typical amount of binder in the ceramic is 2-3 weight %. Due to their low content of [[sodium]] they are suitable for preparation of [[dielectric materials]], [[piezoelectric]] ceramics, and other special [[electroceramic]]s. As a binder, PPC is available from Novomer Inc., Ithaca, NY USA or Empower Materials Inc., Newark, DE USA under the trade name QPAC-40.[http://www.novomer.com][http://www.empowermaterials.com/news%20article%202.htm]. Polyethylene carbonate or PEC, is commercially available from Empower Materials Inc. under the trade name QPAC-25.
Polypropylene carbonate binders are [[amorphous]], with [[glass transition temperature]] of 40 °C. Polyethylene carbonate has glass transition temperature of 25 °C.
Monomeric [[propylene carbonate]] is used as an organic [[solvent]]. It can be used as a [[plasticizer]], to lower the glass transition temperature of polypropylene carbonate and polyethylene carbonate. It is also a byproduct of manufacture of PPC.
Composites of polypropylene carbonate with [[starch]] ('''PPC/starch''') can be used as a [[biodegradable]] plastic.
[[Category:Plastics]]
[[Category:Polycarbonates]]
[[Category:Biodegradable plastics]]