Trimethylene carbonate, TMC

These representative aliphatic polyesters are often used in copolymerized form in various combinations, for example, poly(lactide-co-glycolide) (PLGA) [66-68] and poly(lactide-co-caprolactone) [69-73], to improve degradation rates, mechanical properties, processability, and solubility by reducing crystallinity. Other monomers such as 1,4-dioxepan-5-one (DXO) [74—76], 1,4-dioxane-2-one [77], and trimethylene carbonate (TMC) [28] (Fig. 2) have also been used as comonomers to improve the hydrophobicity of the aliphatic polyesters as well as their degradability and mechanical properties. 

Kinetic measurements of the ring-opening polymerization of trimethylene carbonate (TMC) versus the enchainment of oxetane and CO2 to provide poly (TMC) reveal that these processes in the presence of (salen)CrCl and an ammonium salt have similar free energies of activation (AG ) at 110°C. This similarity in reactivity coupled with the observation that in situ infrared studies of the copolymerization of oxetane and CO2 showed the presence of TMC during the early stages of the reaction has led to the overall mechanism for copolymer production shown in... 

In recent years, homoleptic lanthanide(III) tris(amidinates) and -guanidinates have been demonstrated to exhibit extremely high activity for the ROP of polar monomers such as e-caprolactone (CL) and trimethylene carbonate (TMC) (cf.. Sect. 4.2) [6,7]. 

In addition lipase-catalyzed ROP of lactones was successfully used to synthesize macromers by using hydroxyl moieties of carbohydrates as sites for initiation [68, 69, 88], Specifically, ethylglucopyranoside (EGP) was used as a multifunctional initiator and e-CL/trimethylene carbonate (TMC) as monomers for lipase-catalyzed ROPs. Initiation of ROP occurred selectively from the 6-hydroxyl position forming macromers with a carbohydrate head group with three remaining hydroxyl groups that remained available for other enzymatic or chemical transformations (Scheme 4.13). 

Aliphatic polycarbonates are a class of surface erosion biodegradable polymers attracting great interests due to their good biocompatibility, favorable mechanical properties and low toxicity (18,19), The polymerization of aliphatic cyclic carbonates such as trimethylene carbonate (TMC) have been extensively studied (20,21). 

Polymerization of lactones such as glycolide (G), 1-lactide (LL), dl-lactide (DL-L), p-dioxanone (PD), trimethylene carbonate (TMC), e-caprolactone (CL), 1,5 dioxepan-2-one (DOX), glycosalicylate (GS), morpholine-2,5-dione (MD)... 

In a study by Carpenter and co-workers, two types of copolyesters were made to determine the effect of a basic central group on the properties of the polymer.il Accordingly, triethanolamine (TEA) and trimethylolpropane (TMP) were used to prepare the polyaxial initiator with central amine and carbon atoms, respectively, using trimethylene carbonate (TMC) and capro-lactone (CL) as comonomers. 

For this group of new polymers, a prepolymeric polyalkylene succinate was prepared, end-grafted with e-caprolactone (CL) and/or trimethylene carbonate (TMC), and the product was then end-grafted with glycolide or a gly-colide-rich mixture of monomers. Discussion in this chapter is focused on these copolyesters based on polytrimethylene succinate. 

Comprising PEG-400 End-Grafted with a Mixture of Trimethylene Carbonate (TMC) and Glycolide.198... 

Trimethylene carbonate (TMC) and glycolide (G) were purchased from Boehringer Ingelheim Chemicals, Inc. (Virginia). Polyethylene glycol-400 (PEG-400) was purchased from Sigma-Aldrich (Missouri). Modified/stabilized methoxypropyl cyanoacrylate tissue adhesive (MS-MPC) was prepared at Poly-Med, Inc. (South Carolina). 

The third class primarily consists of polymers of 1,3-dioxane-2-one otherwise known as trimethylene carbonate (TMC) and its copolymers with glycolide and lactide. PTMC degrades at a much slower rate than PGA. In addition, it softens between 40 °C and 60 °C, has low mechanical strength [5], and is reported to improve handling properties in copolymers with PGA [4]. Some thermal and mechanical properties of PTMC are shown in Table 55.1. 

Trimethylene carbonate (TMC) PEEK Polyurethanes Ceramics Silicone... 

Copolymers of PLA and PGA tend to be less crystalline and less hydrophobic than the homopolymer and subsequently have shorter degradation times. Poly(lactide-co-glycolide) (PLGA) has been used extensively for drug delivery and device manufacture." Copolymers of glycolide with trimethylene carbonate (TMC), called polyglyconate, have been used as sutures (Maxon ) and as screws." ... 

Al-Azemi, T.F., Harmon, J.P., Bisht, K.S., 2000. Enz3mie-catalyzed ring-opening copolymerization of 5-methyl-5-benzyloxycarbonyl-l,3-dioxan-2-one (MBC) with trimethylene carbonate (TMC) synthesis and characterization. Biomacromolecules 1, 493—500. 

Block terpolymers containing a random soft middle block copolymer of p-dioxanone and trimethylene carbonate (TMC) and polyglycolic acid (PGA) end blocks were prepared (Roby et al, 1995) as shown in Figure 14. 

The stereocopolymers of lactic acid, prepared by the polymerization of various stereoisomers, are discussed in a subsequent section in this book and will not be discussed here. Typical comonomers that have been used for lactic acid or lactide copolymerization are glycolic acid or glycolide (GA) [11-17], poly (ethylene glycol) (PEG) or poly(ethylene oxide) (PEG) [15 3], poly(propylene oxide) (PPO) [16-18], (7 )- 3-butyrolactone (BL), 6-valerolactone (VL) [44-46], E-caprolactone (CL) [47-54], 1,5-dioxepan-2-one (DXO) [55-60], trimethylene carbonate (TMC) [61],... 

Trimethylene carbonate, TMC, is a commonly used co-monomer for poly(glycolide-c -lactide) base sutures [57,58]. Incorporation of the carbonate structure provides flexibility and toughness to the otherwise rigid and brittle copolyesters. 

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