Dental Materials Exam 2

Polymerizes via a condensation reaction of SH and an oxidizing PbOby product: H2Onot commonly used

Polymerizes via a condensation reaction of OH with stannous octate by product: ethyl alcohol not commonly used

Polymerization reaction called hydrosilylation. involves C=C and Pt salt catalyst, oxidative addition By product: None, but can give off H in damp environments retarded by S Very accurate and stable expensive

Cationic polymerization - oxygen in the chains By product: noneRing opening reaction - offset polymerization shrinkagevery accurate and stable tastes like crap epinephrine and iron sulfate inhibit set fastest set absorb waterexpensive

Na3PO4 retarderCaSO49 reactorKTiF accelerator diatomaceous earth with glycerine (dustless)

Impression PastesSaponification reaction, COOH of carboxylic (fatty) acids react with cation of ZnOwater is an accelerant
-no teeth!SnO (base) and oilEugenol (acid), resins and filler
same as cements: Acid + Base --> Salt + wateruses: perio packs and bite registration materials

Secondary bonds dominate

ZOE Impression pastes -COOH of carboxylic acids react with cation from ZnO you make salt!!!!!

1800 filler- released F but dissolved away

1940s polymerization shrinkage

1960s birth of modern composites

How much of the stress/strain is transferred from one phase to another

Covalent -Si-O-Si- bondThe goal of silanization is to form bonds across the interface between mineral components and organic components present in paints, adhesives..

Addition (free radical) polymerization (same as acrylics)

Sealants