The invention relates to polyisocyanates that have aliphatically, cycloaliphatically, araliphatically and/or aromatically bonded isocyanate groups and contain thioallophanate structures of formula (I),

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to a method for producing them, and to their use as starting components in the production of polyurethane plastics.

A biodegradable scaffold, a low-molecular weight thioketal, and a method of forming a biodegradable scaffold are provided. The biodegradable scaffold includes a thioketal and an isocyanate, where the thioketal is linked to the isocyanate to form the scaffold. The low-molecular weight thioketal includes 2,2-dimethoxypropane and thioglycolic acid, wherein the thioketal includes at least two hydroxyl terminal groups. The method of forming the biodegradable scaffold includes blending a thioketal with an excess isocyanate, forming a quasi-prepolymer, mixing the thioketal, the quasi-prepolymer, and a ceramic, and then adding a catalyst to form the biodegradable scaffold. The thioketal is a low-molecular weight thioketal having at least two hydroxyl terminal groups.

Dental material, which contains an ene compound with two or more CC multiple bonds and a thiol according to general Formula (1) or an oligomer based on such a thiol,

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wherein n, p and m are chosen such that the thiol has a total of at least 3 SH groups.

The present invention relates to a method of fast curing a polythiourethane based transparent casted substrate. comprising in a preferred embodiment providing a first component A comprising a polythiourethane pre-polymer Al having isocyanate or isothiocyanate end groups. providing a second component B comprising a polythiourethane pre-polymer BI having thiol end groups. mixing together first and second components A and B and filling a molding cavity of a casting mold assembly with the resulting mixture. curing said mixture to obtain a transparent substrate, wherein at least one latent catalyst that is heat-activatable is added in the process prior to curing step 4). and said catalyst is subsequently activated to accelerate the polymerization reaction forming the polythiourethane based transparent substrate.