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Hybrid polymers (ORMOCERO®s, Ceramers) are composites with inorganic and organic
nanobuilding blocks linked via stable covalent bonds based on organically
modified silicon alkoxides and/or functionalized organic oligomers/polymers.
A method often used is the formation of the inorganic network by polycondensation
reactions (e.g. Si-O-Si bond formation) in a first step, followed by the organic
crosslinking (thermal curing at 80–180 °C or UV-processing). Another type
uses the silylation of organic polymers, with subsequent hydrolysis and
polycondensation reactions of the silanized units.
The paper focuses on the selection of precursors for various applications and the
chemistry involved in processing. Basic properties and the application potential
of ORMOCERO®s as coatings, fibers and composites are presented.
Property/composition relationships are shown for mechanical and
permeation/barrier properties.
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