Terpene/isoolefin copolymers having substantially heterogeneous compositional distribution and displaying thermoplastic elastomeric properties

Abstract

Copolymers having a substantially heterogeneous composition distribution and strong UV absorption comprise the direct reaction product of an isoolefin and at least one terpene having the molecular formulae of (C 5 H 8 )n where n is equal to or greater than two, and optionally additional monomers. More specifically, the invention relates to copolymers of isobutylene and alloocimene that exhibit thermoplastic elastomeric properties and exhibit strong filler interaction. The present invention also relates to methods for producing copolymers of at least one isoolefin and at least one terepene by a two-phase living polymerization that produces a substantially linear diblock, triblock, and multiblock copolymer having substantially heterogeneous distribution of the isoolefin and terpene units.

1 . A thermoplastic elastomer (TPE), comprising:
 a linear, diblock, or triblock, or multiblock copolymer, or any combination thereof, having repeat units derived from at least one isoolefin monomer having from 4 to about 7 carbon atoms, and repeat units derived from at least one terpene monomer having the formula (C 5 H 8 )n wherein n is 2 or more; and optionally repeat units derived from one or more dienes, styrene or a derivative thereof, indene or a derivative thereof, or any combination thereof.   
     
     
         2 . The TPE of  claim 1 , wherein the weight average molecular weight of said block copolymer is at least about 1,000 to about 5,000,000 g/mol. 
     
     
         3 . The TEP of  claim 2 , wherein the weight average molecular weight is from about 200,000 to about 1,000,000 g/mol, wherein said isoolefin is 2-methyl propene (isobutylene), 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene and any combination thereof, and wherein said terpene is myrcene, ocimene, alloocimene, neo-alloocimene, farnesene, 4,8-dimethyl-1,3,7-nonatriene, haslene, squalene, or any combination thereof. 
     
     
         4 . The TPE of  claim 3 , wherein said terpene is myrcene, ocimene, alloocimene, neo-alloocimene and any combination thereof, and wherein said weight average molecular weight is from about 300,000 to about 800,000 g/mol. 
     
     
         5 . The TPE of  claim 4 , wherein said isoolefin is isobutylene, and wherein said terpene is alloocimene, or neo-alloocimene, or any combination thereof. 
     
     
         6 . The TPE of  claim 2 , wherein said TPE has a UV adsorption at about 240 nanometers and said UV adsorption is at least twice as intense as that of the polymer made in the absence of said terpene. 
     
     
         7 . The TPE of  claim 1 , wherein said optional monomer comprises 2-methyl-butadiene-1,3 (isoprene), butadiene, 2-methylbutadiene, 2,4-dimethylbutadiene, piperyline, β-pinene, 3-methyl-1,3-pentadiene, 2,4-hexadiene, 2-neopentylbutadiene, 2-methyl-1,5-hexadiene, 2,5-dimethyl-2,4-hexadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,6-heptadiene, cyclopenta-diene, methylcyclopentadiene, cyclohexadiene, 1-vinyl-cyclohexadiene, styrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, p-methoxystyrene, indene, indene derivatives, or any combination thereof. 
     
     
         8 . The TPE of  claim 4 , wherein the optional monomer comprises isoprene, butadiene, p-methylstyrene, styrene, α-methylstyrene, p-chlorostyrene, p-methoxystyrene, indene, and mixtures thereof. 
     
     
         9 . (canceled) 
     
     
         10 . The TPE of  claim 4 , including a filler comprising silica, carbon black, carbon nanotubes, starch, cellulose, fullerene, nanoclay, or any combination thereof. 
     
     
         11 . The TPE of  claim 11 , wherein the amount of said filler is from about 1 to about 50 parts by weight based upon the total weight of all said diblock, triblock, or multiblock copolymers. 
     
     
         12 . A biomedical composition comprising the TPE of  claim 1 . 
     
     
         13 . A biomedical composition comprising the TPE of  claim 11 . 
     
     
         14 . A drug eluting coating or fiber mat comprising the composition of  claim 1 . 
     
     
         15 . An inner tube or a tubeless tire comprising the composition of  claim 1 . 
     
     
         16 . A process for making a linear thermoplastic elastomer (TPE) block copolymer comprising the steps of: reacting at least one type of an isoolefin monomer having from 4 to about 7 carbon atoms with at least one type of a terpene monomer having the formula (C 5 H 8 )n wherein n is 2 or more and optionally one or more dienes, styrene or a derivative thereof, or indene or a derivative thereof, by a living two-phase carbocationic polymerization in an emulsion, and producing a linear, diblock, or triblock, or multiblock, or any combination thereof, copolymer. 
     
     
         17 . The process of  claim 16 , wherein the weight average molecular weight of said block copolymer is from about 1,000 to about 5,000,000 g/mol, wherein said isoolefin is 2-methyl propene (isobutylene), 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene, or any combination thereof, and wherein said terpene is myrcene, ocimene, alloocimene, neo-alloocimene, farnesene, 4,8-dimethyl-1,3,7-nonatriene, haslene, squalene, or any combination thereof. 
     
     
         18 . The process of  claim 17 , wherein the weight average molecular weight of said block copolymer is from about 200,000 to about 1,000,000 g/mol, wherein said polymerization is an emulsion polymerization free of any additional emulsifying agents. 
     
     
         19 . The process of  claim 18 , wherein said isoolefin is isobutylene, wherein said terpene is alloocimene, or neo-alloocimene, or any combination thereof, and including polymerizing optional monomers comprising 2-methyl-butadiene-1,3 (isoprene), butadiene, 2-methylbutadiene, 2,4-dimethylbutadiene, piperyline, β-pinene, 3-methyl-1,3-pentadiene, 2,4-hexadiene, 2-neopentylbutadiene, 2-methyl-1,5-hexadiene, 2,5-dimethyl-2,4-hexadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,6-heptadiene, cyclopenta-diene, methylcyclopentadiene, cyclohexadiene, 1-vinyl-cyclohexadiene, styrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, p-methoxystyrene, indene, indene derivatives, or any combination thereof. 
     
     
         20 . The process of  claim 19 , wherein said polymerization includes the utilization of a Lewis acid catalyst, optionally a cation source and a diluent that does not dissolve said bock copolymer, and wherein said molecular weight of said block copolymer is from about 300,000 to about 800,000 g/mol. 
     
     
         21 . The process of  claim 18 , wherein said polymerization includes the utilization of an aluminum trichloride catalyst, wherein the amount of said catalyst is from about 0.001 to about 5.0 parts by weight per 100 parts by weight of said monomers, from about 0.00001 to about 5.0 parts by weight of water as a cation source per 100 parts by weight of said monomers, and a methyl chloride diluent, wherein said isoolefin is isobutylene, wherein said terpene is alloocimene or neo-alloocimene or any combination thereof and wherein said weight average molecular weight is from about 300,000 to about 800,000 g/mol.