MPDiol Glycol is used in the production of polyethylene terephthalate (PET).
PET is produced by the condensation polymerization of ethylene glycol (EG) with terephthalic acid (TPA) or dimethylterephthalate (DMT).
The use of PET in the production of fibers, films and containers has grown to 75 billion lbs. per year1. The molecular weight of PET polymers is an important characteristic used to define their utility in these applications. PET polymers can be further differentiated through chemical modification, thereby enhancing their properties and/or processability. This is typically accomplished by copolymerizing with modest additions of glycols such as diethylene glycol (DEG), cyclohexanedimethanol (CHDM), polyethylene glycol (PEG) or diacids such as isophthalic acid (IPA)2.
Benefits and Applications
MPDiol glycol has been found to be particularly effective in the chemical modification of PET used in fiber3 and film production. When copolymerized with a relatively low level of MPDiol glycol, PET copolymer spun into fiber exhibits increased dye uptake, deeper color and softer hand versus PET homopolymer. MPDiol glycol-copolymerized PET has also been shown to increase productivity, allowing for higher spinning speeds without sacrificing fiber quality.
Further processing cost reduction is possible via reduced melt processing temperatures and lower dye consumption rates.
When extruded into film, MPDiol glycol-copolymerized PET demonstrates improved clarity, toughness, elongation and shrinkage. In both fiber and film applications, MPDiol glycol appears to be a very cost-effective alternative to other modifying comonomers.
References
1 BP Petrochemicals Europe; Polyester 2003 - 8th World Congress; Zurich, Switzerland.
2 Nichols, C.S., Humelsine, B.M., US Patent 6,485,829 B2 (Nov. 26, 2002).
3 a) Toga, Y.;Shimada, T.; Okamoto, I., US Patent 4,415,727 (1983). b) Chen, S.C.; Lin, F.S.; Chou, J.-Y.; Wang, H.Y.; Lee, M.S.; Chen, M.-S.; Huang, Y.J.; Sun, H.S., US Patent 5,916,677 (1999).
MPDiol is a trademark owned or used by LyondellBasell group companies. Trademark MPDiol is registered in the U.S. Patent and Trademark Office.