Monomers Issued From Renewable Resources and Process for Polymerising Them

Abstract

Polycarbonates prepared from carbonate monomers derived from the biomass are synthesized in the presence of an organometallic transfer agent and an alcohol. The number average molecular weight Mn of the final polymer increases with increasing the monomer/alcohol ratio.

1 . A process for comprising:
 selecting an amount of alcohol to obtain a monomer/alcohol ratio ranging between 25 and 25000, wherein the monomers comprise five- or six- or seven-membered cyclic carbonates; and   polymerizing the five- or six- or seven-membered cyclic carbonates by ring-opening polymerisation in the presence of a system comprising an organometallic compound and the alcohol, said process being characterised in that the number average molecular weight Mn of the final polymer increases with increasing the monomer/alcohol ratio.   
     
     
         2 . The process of claim wherein the organometallic compound is selected from metallic complexes of formula MR, wherein M is a metal Group 2, 3, 8, 12 or 13 of the periodic table, wherein each R is selected independently from hydrogen, a linear or branched hydrocarbyl radical having from 1 to 12 carbon atoms, an alkoxide group OR* wherein R* is a linear or branched hydrocarbyl having from 1 to 12 carbon atoms, an amido group NR**2 wherein each R** is independently of general formula YR #   3  wherein Y is Si or C and each R #  is independently selected from hydrogen or hydrocarbyl having from 1 to 12 carbon atoms, a borohydride group or an halide, and wherein n is the valence of M. 
     
     
         3 . The process of  claim 2 , wherein M is Mg(II), Ca(II), Y(III), Fe(II), Fe(III), Zn(II), or Al(III). 
     
     
         4 . The process of  claim 2 , wherein each R is selected independently from an amido group, an alkoxide group OR′, or a borohydride group (BH 4 ). 
     
     
         5 . The process of  claim 1 , wherein the organometallic compound is a single-site catalyst component based upon a bulky β-diiminate ligand (BDI) represented by general formula 
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6  and R 7  are each independently selected from hydrogen, unsubstituted or substituted hydrocarbyl, or inert functional group, wherein two or more of said groups can be linked together to form one or more rings, wherein X is an hydrocarbyl radical having from 1 to 12 carbon atoms, an alkoxide group OR*, an amido group NR** 2  or a borohydride group (BH4). 
       
     
     
         6 . The process of  claim 1 , wherein the organometallic compound is selected from [BDI]Zn(N(SiMe 3 ) 2 ), {[BDI]Zn(OiPr),} 2 , Zn(N(SiMe 3 ) 2 ), ZnEt 2 , Y(N(SiMe 3 ) 2 ), “Y(OiPr) 3 ”, and Al(OiPr) 3.    
     
     
         7 . The process of  claim 1 , wherein the alcohol is R′OH wherein R′ is an hydrocarbyl, linear or branched, having from 1 to 20 carbon atoms. 
     
     
         8 . The process of  claim 7 , wherein the alcohol is isopropyl ( i Pr) or benzyl (Bn). 
     
     
         9 . The process of  claim 1 , wherein the alcohol contains a functional group that caps the end of each polycarbonate chain. 
     
     
         10 . The process of  claim 1 , wherein the amount of metal catalyst is selected to obtain a ratio monomer/metal of from 1000 to 100000. 
     
     
         11 . The process of  claim 1 , wherein the final polymer is a homo- or co-polymer of carbonate and wherein the carbonate is a 5- or 6-membered cyclic carbonate selected from trimethylenecarbonate (TMC), 2-benzyloxy-trimethylenecarbonate (BTMC), 2-hydroxy-trimethylenecarbonate (TMCOH), 4-(benzyloxymethyl)-1,3-dioxolan-2-one (BDMC), 4-(hydroxymethyl)-1,3-dioxolan-2-one (DMCOH), 2-oxy-trimethylenecarbonate (OTMC), dehydrotrimethylenecarbonate (DHTMC), or a combination thereof. 
     
     
         12 . (canceled) 
     
     
         13 . A homo- or co-polymer of carbonates obtained by the process of  claim 1 . 
     
     
         14 . The process of  claim 1 , wherein the amount of the alcohol is selected to obtain a monomer/alcohol ratio ranging between 25 to 250. 
     
     
         15 . The process of  claim 1 , wherein the amount of the alcohol is selected to obtain a monomer/alcohol ratio ranging between 200 and 2500. 
     
     
         16 . The process of  claim 1 , wherein the number average molecular weight Mn of the final polymer is tuned by the monomer/alcohol ratio to range from 1,000 to 1,000,000 g/mol. 
     
     
         17 . The process of  claim 1 , wherein the number average molecular weight Mn of the final polymer is tuned by the monomer/alcohol ratio to range from 10,000 to 250,000 g/mol. 
     
     
         18 . A process comprising:
 polymerizing five- or six- or seven-membered cyclic carbonates by ring-opening polymerisation in the presence of a system comprising an organometallic compound and an alcohol; and   tuning a number average molecular weight Mn of the final polymer to range from 1,000 to 1,000,000 g/mol, wherein the number average molecular weight Mn of the final polymer is tuned by selecting an amount of the alcohol to obtain a monomer/alcohol ratio ranging between 25 and 25000, said process being characterised in that the number average molecular weight Mn of the final polymer increases with increasing the monomer/alcohol ratio.