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Sweden's Perstorp (U.S. office in Toledo, Ohio; perstorp.com); as well as biobased plasticizers, such as a new line of soy-based plasticizers sold under the Vikoplast designation by Arkema, and long-standing citric-acid-derived Citroflex plasticizers from Vertellus. Other available alternatives that continue to draw interest include TOTM (trioctyl trimellitate) and polymeric plasticizers from BASF, Eastman, and others. These two groups of non-phthalates have been given a green light for low plasticizer migration in medical-device components made of ABS, PC, PS, and acrylic that come in contact with PVC components. DOTP, HEXAMOLL DINCH IMPROVEMENTS DOTP and Hexamoll DINCH are two leading non-phthalate alter- natives gaining significant ground. DOTP from Eastman has been available for several decades as Eastman 168, and the com- pany claims it is the market-leading non-phthalate plasticizer for PVC, offering performance equal to or better than most non- phthalates. It offers good performance properties, optimal low- temperature flexibility, and non-migration properties. In 2013, Eastman launched the 168 SG (sensitive grade) version. This enhanced, high-purity grade offers the most stringent quality- assurance protocols for sensitive applications that include medical and children's products. Brucks says Eastman is seeing a nine-fold increase in consump- tion of DOTP plasticizers in medical applications. Since its commercial introduction, 168 SG has been used in a wide range of sensitive applications, including IV infusion sets, blood/IV bags, tubing, childcare articles, and food- contact products. Eastman sees its DOTP plasticizers as offering an easy replacement for DEHP and TOTM. Advantages cited include: • Dry time fairly similar to that of DINP, and better than Hexamoll DINCH. • Efficiency fairly similar to DINP and DINCH, while slightly lower than DEHP. • Slightly longer dry-blending time with low-speed mixers than comparable plasticizers. • Improved low-temperature brittleness compared with alternative offerings. BASF launched Hexamoll DINCH in 2002. Thanks to its excellent toxicological profile and low migration rate, this additive has become an established plasticizer in PVC food packaging, medical devices, and toys. More recently, BASF reports that demand has also increased in floor and wall coverings as well as fitness equipment. In 2014, BASF doubled its capacity to 442 million lb/yr as a result. At the same time, BASF also saw the value of DOTP, and launched Palatinol DOTP in 2013. Moreover, last year the company announced that it would start production of DOTP in North America in 2017 with dedicated product facilities in Pasadena, Tex. According to Napiany, the project will help meet the growing demand for non-ortho-phthalate plasticizers in North America, and will strengthen BASF's position in this fast-growing market. BASF is also expanding its 2-EH capacity along with the DOTP investment, ensuring reliable feedstock integration for DOTP. Asked what prompted the Palatinol DOTP introduction, in view of Hexamoll DINCH's success, Napiany explains that DINCH has found use in medical devices and other medical plastics, while demand for DOTP has continued to grow in North America in a number of other important market segments. Included are flooring, film and sheet, consumer products, including some toys, and tubing for beverages. BASF concedes that slightly higher processing temperatures are required for both DOTP and Hexamoll DINCH than for DEHP and DINP. For some processes, such as extrusion and injection molding, this is not a factor since the typical processing temperatures are more than sufficient. Plastisol processing does require somewhat higher temperatures than with conventional phthalates. In addition, Hexamoll DINCH has some inherent lubricating properties, so the use of other lubricants such as stearates may be reduced or eliminated. Hexamoll DINCH and DOTP have both been extensively tested using the latest Organization for Economic Cooperation and Development (OECD) and other testing protocols. Both plasticizers present no relevant hazards to humans or the environment, as confirmed by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) in 2015 and other government authorities such as the European Food Safety Authority (EFSA). BASF's Napiany notes that while plasticizers like DOTP and DINCH are fairly comparable to DEHP, compounders must keep in mind that plasticizers are always a little different from each other. For example, slight modifications to the formulation and process are necessary to optimize the quality of the finished article. "Most customers in vinyl formulation are able to make these adjustments quite easily. In addition, the BASF technical service group offers "We are seeing push- back in Europe for no phthalates in wire and cable that go into toys and electronic gadgets. This is also catching on in North America." Vertellus' Citroflex citric- acid-based plasticizers reportedly have broader regulatory approvals in medical applications than other biobased plasticizers. 44 AUGUST 2016 Plastics Technology PTonline.com ADDITIVE S