A polycarbonate, a preparation method thereof, and an application thereof are provided. First, an ureido-pyrimidinone type diisocyanate is prepared by a first compound and a second compound. Then, a third compound and the ureido-pyrimidinone type diisocyanate are reacted to obtain a polycarbonate. The polycarbonate replaces scratch resistant metal material to avoid the disadvantages of the signal shielding, heavy weight, and static electricity when using the scratch resistant metal material in the winter. The body housing is made of polycarbonate can have a self-healing property and a good heat resistance, so the internal components can be well protected.

A biocompatible nerve conduit for nerve re-generation, wherein a porous fiber tube is coated with a bioresorbable hydrogel, with the fibers being formed from a polymer that supports nerve regeneration by preferential adsorption of endogenous proteins and braided with pores in the range from 5 to 200 micrometers using a kink-resistant braiding pattern and the hydro gel coating material and thickness being selected to control the overall porosity, so that nutrients and oxygen can diffuse through said hydrogel coating but the infiltration of fibrous tissue through the coating is prevented.

A biocompatible nerve conduit for nerve re-generation, wherein a porous fiber tube is coated with a bioresorbable hydrogel, with the fibers being formed from a polymer that supports nerve regeneration by preferential adsorption of endogenous proteins and braided with pores in the range from 5 to 200 micrometers using a kink-resistant braiding pattern and the hydro gel coating material and thickness being selected to control the overall porosity, so that nutrients and oxygen can diffuse through said hydrogel coating but the infiltration of fibrous tissue through the coating is prevented.

A thermoplastic composition comprises: a copolycarbonate comprising bisphenol A carbonate units and second carbonate units of the formula (I) and optionally, a bisphenol A homopolycarbonate; wherein the second carbonate units are present in an amount of 10 to 49 mol % based on the sum of the moles of the copolycarbonate and the bisphenol A homopolycarbonate, the copolycarbonate comprises less than 2 ppm by weight of each of an ion of lithium, sodium, potassium, calcium, magnesium, ammonium, chlorine, bromine, fluorine, nitrite, nitrate, phosphite, phosphate, sulfate, formate, acetate, citrate, oxalate, trimethylammonium, and triethylammonium, as measured by ion chromatography, and the thermoplastic composition has a bisphenol A purity of at least 99.6%, or at least 99.7% as determined by high performance liquid chromatography. The thermoplastic composition has a Vicat B120 of 155 C. or higher; and an increase in yellowness index of less than 10 during 1000 hours of heat aging at 155 C. ##STR00001##

A thermoplastic composition comprises: a copolycarbonate comprising bisphenol A carbonate units and second carbonate units of the formula (I) and optionally, a bisphenol A homopolycarbonate; wherein the second carbonate units are present in an amount of 10 to 49 mol % based on the sum of the moles of the copolycarbonate and the bisphenol A homopolycarbonate, the copolycarbonate comprises less than 2 ppm by weight of each of an ion of lithium, sodium, potassium, calcium, magnesium, ammonium, chlorine, bromine, fluorine, nitrite, nitrate, phosphite, phosphate, sulfate, formate, acetate, citrate, oxalate, trimethylammonium, and triethylammonium, as measured by ion chromatography, and the thermoplastic composition has a bisphenol A purity of at least 99.6%, or at least 99.7% as determined by high performance liquid chromatography. The thermoplastic composition has a Vicat B120 of 155 C. or higher; and an increase in yellowness index of less than 10 during 1000 hours of heat aging at 155 C. ##STR00001##

A thermoplastic composition including a copolycarbonate comprising bisphenol A carbonate units and second carbonate units of the formula

##STR00001##

wherein R.sup.a and R.sup.b are each independently a C.sub.1-12 alkyl, C.sub.1-12 alkenyl, C.sub.3-8 cycloalkyl, or C.sub.1-12 alkoxy, each R.sup.3 is independently a C.sub.1-6 alkyl, R.sup.4 is hydrogen, C.sub.2-6 alkyl or phenyl optionally substituted with 1 to 5 C.sub.1-6 alkyl groups, p, q, and j are each independently 0 to 4, optionally a bisphenol A homopolycarbonate; and an acid stabilizer comprising a sulfonic acid ester; wherein the composition has an improved volatile or non-volatile organic compound content and yellowness index value when compared to a reference sample of an otherwise identical composition except for not containing the stabilizer.

Provided is a polycarbonate-based resin having a ratio of an amine terminal to all terminal groups of 1.0 mol % or more.

Provided is a polycarbonate copolymer including a repeating unit of the following Chemical Formula 1, where the polycarbonate copolymer can have improved heat resistance:

##STR00001##

wherein in Chemical Formula 1, R.sub.1, R.sub.2, n1 and n2 are as defined in the specification.

Provided is a polycarbonate copolymer including a repeating unit of the following Chemical Formula 1, where the polycarbonate copolymer can have improved heat resistance:

##STR00001##

wherein in Chemical Formula 1, R.sub.1, R.sub.2, n1 and n2 are as defined in the specification.

Disclosed are new classes of diphenol compounds, derived from tyrosol or tyrosol analogues, which are useful as monomers for preparation of biocompatible polymers. Also disclosed are biocompatible polymers prepared from these monomeric diphenol compounds, including novel biodegradable and/or bioresorbable polymers of formula

##STR00001## These biocompatible polymers or polymer compositions with enhanced bioresorbabilty and processibility are useful in a variety of medical applications, such as in medical devices and controlled-release therapeutic compositions. The invention also provides methods for preparing these monomeric diphenol compounds and biocompatible polymers.