Synthesis and characterization of isosorbide carbonate-lactide copolymers

POLY 255

Ola Betiku1, Madeline Jenni1, Karl Ludescher1, Eric Meierdierks1, James Lunt, jl@jimluntllc.com2, and Joseph D Schroeder, joe_schroeder@natureworksllc.com1. (1) Process and Technology Group, NatureWorks LLC, 15305 Minnetonka Blvd, Minnetonka, MN 55345, (2) Jim Lunt and Associates LLC, 16008 Adeleine Lane, Wayzata, MN 55391
Poly(Isosorbide carbonate) (PIC) is a high Tg polymer derived from a bio-renewable diol and carbonate source. Poly(lactide) (PLA), a bio-renewable polyester, and PIC can be made miscible by transesterification to give a new composition with a single Tg in good agreement with the Fox equation. The transesterification reaction was carried out in the melt with Sn(2-EHA)2 or in diphenyl ether with Ti(OBu)4. Sufficient transesterification to bring about miscibility occurred in less than 16 minutes at 240 ºC in the melt and less than 80 minutes at 180 ºC in solvent. The reaction could be followed by changes in 1H-NMR and DSC as a function of time. There is good agreement of the thermal and spectroscopic properties of the final samples from both the solvent based and melt transesterification processes. Transesterification was inevitably accompanied by molecular weight averaging. This led to a copolymer with lower molecular weight than the starting PLA due the low molecular weight of the PIC.
 

Polymers from Renewable Resources
8:20 AM-11:45 AM, Monday, August 20, 2007 Westin Boston Waterfront -- Douglas, Oral

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007