Copolyester-amides

Elastomeric biodegradable copolyester amides, (IV), and copolyester urethanes were prepared by Chu et al. (4) and were effective as drug delivery agents. 

Chu C C and Katsarava R (2003), Elastomeric functional biodegradable copolyester amides and copolyester urethanes , US Patent 6,503,538. 

High-performance TPE based on a polyamide (aka nylon) hard block along with a soft segment. PAEs are also known as polyether block amides or as copolyester amides or thermoplastic elastomer-amides. They are used mainly in areas where other TPE cannot compete/ perform, especially at lower temperatures. 

Copolyesters (such as BIOMAX ) which combine aromatic esters with aliphatic esters or other polymer units (e.g. ethers and amides) provide the opportunity to adjust and control the degradation rates. These added degrees of freedom on polymer composition provide the opportunity to rebalance the polymer to more specifically match application performance in physical properties, while still maintaining the ability to adjust the copolyesters to complement the degradation of natural products for the production of methane or humic substances. Since application performance requirements and application specific environmental factors and degradation expectations vary broadly, copolyesters are, and will continue to be, an important class of degradable polyesters. 

TPEs are not listed in packaging statistics there are only specific uses for thermoplastic styrenics (TPS), copolyester TPEs (COPE) and polyether bloc amides (PEBA) in tearproof films, and for TPOs and TPVs in seals, etc. 

In condensation polymerization, the reaction starts with two different types of monomers but these polymers are not copolymers. The reason is that the first reaction generally makes an intermediate—an ester or an amide—which is then polymerized into a polyester or a polyamide. Copolyesters and copolyamides incorporate a third monomer. 

It was also found for the copolyesters in which the amide group (from DHBP-A) content exceeded 40 mol%, that the endotherms encountered during the first DSC scan differ from those obtained on subsequent heating run. Therefore it can be concluded that during the heating of the polymer in the DSC to approximately 30-40 C above T ... 

Thermoplastic elastomers (TPEs), which combine the characteristics of both thermoplastics and elastomers, can be classified into two major groups. The first is made up of block copolymers formed by polymerizing a thermoplastic monomer with an elastomer comonomer, as in the case of styrene block copolymers such as styrene-ethylene-butadiene-styrene (SEBS). Engineering TPEs such as thermoplastic urethanes (TPUs), copolyesters (COPEs) and polyether block amides (PEBAs) can be included in this first group. Other types of copolymer are from the polyolefin family, consisting of the polyolefin... 

Polyesters and Polyamides. A number of investigations have shown that the sequence structure of copolyesters and copolyamides is accessible by H, C, or n.m.r. Systems studied ate terephthalic acid-based copolyesters ( H), ethylene glycol-based copolyesters ( H), numerous copolyesters by and C n.m.r., copolyamides ( Q, copolymerized lactams ( C), and numerous polyamides and polyactams by N n.m.r. The carbonyl region in C spectra is particularly valuable for structural analysis, though if the experimental difficulties can be surmounted, N spectra are possibly even more informative about the location of amide groups. - ... 

Fig. 5.8 Melting temperature-composition relations for various copolyesters and copolyamides. , poly(ethylene terephthalate/adipate) o, poly(ethylene terephthalate/sebacate) , poly(hexamethylene adipamide/sebacamide) , poly(hexamethylene adipamide/capro-amide). (From Edgar and Ellery (59), Sonnerskog (60) and Izard (61))...

Method of synthesis various routes can be used to link the three types of monomers Involved, but polycondensation (transesterification) to form copolyesters and polyester amides is the most frequently used Rnk, J K, High Performance Polymers, William Andrew, 2008. 

FIGURE 19 Representative composting time (in months) of biopolymers (TPS - Thermoplastic starch, PC - Polycaprolactone, mc-PHA - medium chain length PHA, Al-co-PEs -Ahphatic co-polyester, PEA - Polyester amides, Ah/arocoPEs - Aliphatic/aromatic copolyester, and CDAc - Cellulose diacetate). 

The most important examples of thermoplastic elastomers include TPE-0 (polyolefin-based TPE), TPE-A (polyether(ester)-block-amide), TPE-E (copolyester-based TPE), TPE-S (styrene copolymer-based TPE), and TPU (polyurethane-based TPE). 

That means that biopolymers do not have to come exclusively from renewable resources. Bio-degradable biopolymers can also be manufactured from petrochemical raw materials, such as polyvinyl alcohols, polycaprolactone, copolyester, polyester amide. On the other hand, not all biopolymers based on renewable resources are necessarily bio-degradable, e.g., highly substituted cellulose acetate, vulcanized rubber, casein plastics, or linoleum. 

Synthetic Biodegradable materials ( ) -1- BAK 1095 polyester amide (Bayer, G) -2-ECOFLEX 1,4 butandiol adipinic-dicarbonic and terephthalate copolyester (BASE, G) -3- EASTAR 14766 poly(tetramethylene adipate-co-terephthalate) (Eastman, USA) -4- Bionolle 3000 polybutylene succinate/adipate (Showa, Japan). 

---