Abstract: Methods and apparatuses for dropping a hockey puck (collectively the “system”). The system can facilitate or simulate hockey face-offs. Various embodiments of the system can be configured to provide convenience, portability, stability, and/or consistency for dropping a hockey puck to facilitate a hockey face-off. A frame can support a puck housing and a feed mechanism. The feed mechanism may be configured to feed the hockey puck from the puck housing to a feed chute. A release mechanism can receive the hockey puck from the feed chute. The release mechanism may be configured to release the hockey puck according to a predefined release rate. A power source can be carried by the frame and be configured to power the feed and the release of the hockey puck.

Abstract: High thermal stabilities are achievable in linear or multidimensional sulfone, solvent resistant oligomers by incorporating oxazole, thiazole, or imidazole linkages into the oligomer backbone. Blended oligomers of crosslinking oligomers and noncrosslinking compatible polymers are also described. The oligomers include residues of four-functional compounds of the formula: ##STR1## (or isomers thereof) wherein M=--CO--, --S--, --O--, --SO.sub.2 -- or --(CF.sub.3).sub.2 C--; andY=--OH, --SH, or --NH.sub.2.In an improved method, the reactants are condensed at or below ambient temperature in the presence of pyridine in a suitable solvent such as N,N'-dimethylacetamide (DMAC).