PTA is a white crystalline solid, which is produced through the oxidation of paraxylene in the presence of a catalyst. To be used in the manufacturing of polyester fiber, it is purified through hydrogenation, crystallization, separation and drying. More than 60% of PTA is used for the manufacturing of polyester fiber. Polyester fiber is applied in various industries, including apparel, home furnishings and equipment. Approximate 30% of total PTA demand isused for the production of PET in the bottling and audio & video tape industries.
PTA is the designation for the majority of Terephthalic Acid produced in the world today. It is internationally traded and the sales specifications are generally consistent among producers and buyers. The figure below illustrates the structure and appearance of PTA product.
Chemical Structure of Purified Terephthalic Acid
PET is produced by the polymerization of ethylene glycol (EG) and pure terephthalic acid (PTA). EG is a colourless liquid obtained from ethylene, and terephthalic acid is a crystalline solid obtained from paraxylene. When heated together under the influence of chemical catalysts, ethylene glycol and terephthalic acid produce PET in the form of a molten, viscous mass that can be spun directly to fibers or solidified for later processing as plastic.
The presence of a large aromatic ring in the PET repeating units gives the polymer notable stiffness and strength, especially when the polymer chains are aligned with one another in an orderly arrangement by drawing (stretching). In this semi-crystalline form, PET is made into a high-strength textile fibre marketed under such trademarked names as Dacron, the stiffness of PET fibers makes them highly resistant to deformation, so they impart excellent resistance to wrinkling in fabrics. They are often used in durable-press blends with other fibers such as rayon, wool, and cotton, reinforcing the inherent properties of those fibers while contributing to the ability of the fabric to recover from wrinkling.
At a slightly higher molecular weight, PET is made into a high-strength plastic that can be shaped by all the common methods employed with other thermoplastics. Molten PET chips can be blow-molded into transparent containers of high strength and rigidity that are also virtually impermeable to gas and liquid. In this form, PET has become widely used in plastic bottles
Plastic bottles have been the basic necessity for any industry selling liquid products to the consumers. With increasing development of global economy and improvement of the people's living standard, various packing and bottle industry has been developed rapidly. Most types of plastic bottles are made from bottle grade PET chips. So, there is a huge demand for bottle grade PET chips world-wide.
The bottle-grade PET chips are widely used with the following advantages of no poison, no odor, no smell, excellent transparency, low heavy metal content, good color value, stable viscosity, high strength & high isolation and good processing features. In making bottles, the product has a small degradation and low content of acetaldehyde. While ensuring safety and hygiene, it can effectively keep the respectively unique taste of purified water, mineral water and distilled water. Therefore, it becomes the preferred material for package bottles of mineral water bottle, aseptic-filling bottle, carbonate soft drink bottle, edible oil bottle, candy containers and sheet material industry.
End use of Bottle grade chips mainly depends on the Intrinsic Viscosity (IV). PET Chips with IV 0.80 is mainly used for drinking water bottles & mineral water bottles. PET Chips with IV 0.82 is mainly used in making bottles for carbonated drinks, small bottle for edible oil, liquor, medicines & pet sheets as they need better strength & high finished product rate. PET Chips with IV of 0.85 are mainly used for making big packing bottles for carbonated drinks & 3-5 gallons water bottles as these bottles should have good strength & resistance against high pressure.
The polyester fibre and PET bottle are among the major end users of the PET product, contribute 39.84% and 17.14% of the world share in 2015 according to statistics from PCI Wood Mackenzie (refer to Section 2.3.3 for more information).
The development of non-fibre polyester products in the application of packaging is in particular attractive. The market share of PET product used in packaging industry is hopefully reach 20% in 2026 (refer to Section 2.3.3 for more information). The main application is in food industry as hollow bottles or containers for beverage or household purpose.
Bottle-grade PET Chips
Benzoic acid, C6H5COOH, is a colorless crystalline solid and a simple aromatic carboxylic acid. The name is derived from gum benzoin, which was the only known source for a long time. Benzoic acid occurs naturally in many plants and it serves as an intermediate in the biosynthesis of many secondary metabolites.Saltsof benzoic acid are used as food preservatives and benzoic acid is an important precursor for the industrial synthesis of many other organic substances. It is widely used in pharmaceutical industry, food industry and coating industry, mainly used in producing antiseptic medicine, plasticizer, perfume fixative and chemical intermediate, etc.
Chemical Structure of Benzoic Acid
Industrial Grade Benzoic Acid
Specifications for Benzoic Acid