Copolyester forms when modifications are made to polyesters, which are combinations of diacids and diol

Diol

A diol or glycol is a chemical compound containing two hydroxyl groups A geminal diol has two hydroxyl groups bonded to the same atom...

s. For example, by introducing other diacids, such as isophthalic acid

Isophthalic acid

Isophthalic acid is an organic compound with the formula C6H42. This colourless solid is an isomer of phthalic acid and terephthalic acid. These aromatic dicarboxylic acids are used as precursors to commercially important polymers, e.g. the fire-resistant material Nomex...

 (IPA), or other diols, such as cyclohexane dimethanol (CHDM) to the polyester polyethylene terephthalate

Polyethylene terephthalate

Polyethylene terephthalate , commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins often in combination...

 (PET), the material becomes a copolyester due to its comonomer content. .

Copolyesters retain their strength, clarity, and other mechanical properties despite being exposed to a variety of chemicals that typically affect other materials, such as polycarbonate

Polycarbonate

PolycarbonatePhysical PropertiesDensity 1.20–1.22 g/cm3Abbe number 34.0Refractive index 1.584–1.586FlammabilityV0-V2Limiting oxygen index25–27%Water absorption – Equilibrium0.16–0.35%Water absorption – over 24 hours0.1%...

s. This, plus their versatility and flexibility, allows manufacturers to use them effectively in the design of both high-volume, low-cost parts as well as critical, more expensive component parts.

Applications

Copolyester resins have proved to be effective in packaging applications, due to their toughness, versatility and chemical resistance. They are also frequently used in the manufacture and packaging of consumer goods and materials. Markets that rely on copolyesters include medical and medical packaging, home appliances, consumer goods (pens, toys, sporting goods, etc.), and cosmetics

Cosmetics

Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

, among others..,

Versatility of Copolyesters

Copolyesters offer versatility to meet a wide variety of applications.

Glycol + Acid
EG TPA
CHDM IPA
| |
(Poly)ester + Water
| | | | |
PET | PTCG | PCTA
TPA+EG | TPA+CHDM+EG | TPA+IPA+CHDM
| |
PETG PCT
TPA+EG+CHDM TPA+CHDM

Manufacturers

The main global manufacturers and suppliers of Copolyester resins include

• Eastman Chemical Company
  Eastman Chemical Company
  Eastman Chemical Company is a United States based chemical company, engaged in the manufacture and sale of chemicals, fibers, and plastics. Eastman has 11 manufacturing sites in seven countries, supplying its products throughout the world...
  
  

• Bostik
  Bostik
  Bostik is an international adhesives company, a subsidiary of the French oil and gas company Total S.A., head-quartered at Paris. The company was created as Bostik Findley in 2001 after the merger of Bostik and Ato Findley, following the merger of their parent companies, Total Fina and Elf...
  
   Findley

• Toyobo
  Toyobo
  is one of Japan's top makers of fibers and textiles, including synthetic fibers and natural fibers, such as cotton and wool. The company's textiles are designed for clothing, home furnishings, and for industrial uses. Its textiles include spandex yarn for apparel, polyurethane fiber for pantyhose,...
  
  

• Evonik

• SK Chemicals