Polybutylene terephthalate chemical structure

Polyesters form via a condensation reaction between a dicarboxylic acid and a dialcohol to create an ester linkage, as shown in Fig. 24.1. By far, the two most common polyesters are polyethylene terephthalate and polybutylene terephthalate, the chemical structures of which are shown in Fig. 24.2. These two polymers differ from one another by the length... 

The matrix is a biodegradable and aromatic copolyester (polybutylene adipate-co-terephthalate, PBAT), from Eastman (EASTAR BIO Ultra Copolyester 14766). Copolyester chemical structure is given in Table 17.2. This copolyester is soluble at room temperature in different solvents such as THF, CH2CI2, or CHCI3. Determined by HNMR, PBAT composition is 43% of butylene terephthalate and 57% of butylene adipate. Determined by size exclusion chromatography (SEC), molecular weight (Mw) and polydispersity index (IP) are 48,000 and 2.4, respectively. Melt flow index (MFI) is 13 g/10 min at 190°C/2.16 Kg. PBAT density is 1.27 g/cm at 23°C. 

The majority of fiber-forming polymers, like common plastics, are based on petrochemical sources. Polymeric fibers can be produced from the following materials polyamide nylon, polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) polyesters, phenol-formaldehyde (PF), polyvinyl alcohol (PVA), polyvinyl chloride (PVC), and polyolefins (polypropylene (PP) and polyethylene (PE)) among others. Because of the different chemical structures of fiber-forming polymers, their applications vary widely according to the temperature and chemical conditions which they can withstand. For example, polyethylene melts into a viscous liquid at temperatures equal to or less than that of a domestic dryer and therefore its application in a product that will require normal laundering is not possible. However, its fibers can be used in making disposable non-woven products. ... 

---