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Dedication to Polyolefins

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Dedication to Polyolefins Advertorial Dedication to Polyolefins he Spanish-based PE: Polymer Char often collabo - by testing each separately? maker of test instru - rates with its customers to develop Monrabal: Absolutely, because ments for poly - custom instruments, which later the combination also provides the olefins, Polymer become commercial. What’s the interdependence between compo - Characterization most unusual of these? sition and molar mass. Not every S.A. (www.polymer - Monrabal: Probably our most resin needs this, however. For char.com), is extend - unusual collaboration was with homopolymer PP or PE, GPC ing its product range Mitsubishi Chemical in Japan. alone is enough, and for simple Tbeyond its original instruments for Mitsubishi had successfully com - PE/PP copolymers CCD alone large resin producers’analytical mercialized a combined TREF may be enough. CFC testing pro - labs. Polymer Char (pronounced and GPC/SEC instrument, but vides the full picture of more ‘car’) will shortly introduce its first wanted to leave the test instru - complex resins. smaller instruments designed specif - ment market. We partnered to ically for processors’ and resin pro - develop a modern, fully automat - PE: How detailed are Polymer ducers’ quality control labs. Plastics ed version of their instrument, Char’s tests for polyolefin chain Engineering asked the company’s known as CFC (Cross branching? founder and director of R&D, Dr. Fractionation Chromatograph). Monrabal: Long chain branching Benjamin Monrabal, to explain is measured much the same by all some of the unusual technologies PE: Do you get more information GPC instruments, using a triple the company has developed. by testing composition distribution detector (concentration, viscosity and GPC molar mass together than and light scattering). What’s PE: What polyolefin test equipment does Polymer Char build that no one else offers? Monrabal: Most of our instru - ments (except GPC), we are the only provider of. Our CEF (Crystallization Elution Fractionation) instrument devel - oped in 2005, for example, com - bines fast chemical composition distribution analysis (called CRYSTAF) and traditional solu - tion-based CCD testing (called TREF). PE: Why would you combine two chemical composition distribution tests? Monrabal: Complex PP/PE copolymers require both. For example, TREF alone can’t distin - guish a combination of HDPE and EP copolymer, while CRYSTAF alone can’t analyze a combination of HDPE and Ziegler-type PP homopolymer. Polyolefins are get - ting more complicated all the time. 58 | PLASTICS ENGINEERING | SEPTEMBER 2011 | www.4spe.org unique about our GPC is that we solvents manually into a vial or Polymer Char have any instruments add a fourth detector (IR4), dual- change vials externally. for them? wave-length IR, which can meas - Monrabal: By the end of the year ure short chain branching and PE: Your instruments are very spe - we will commercialize several functional groups in polyolefin cialized, yet your GPC One data new instruments specifically for copolymers along the molar mass collection unit accepts data from quality control laboratories. The distribution. We also developed competing GPC instruments as well instruments are simple and reli - an even more sensitive IR5 MCT as your own. Why is that? able and will provide fast analyti - (mercury cadmium telluride) Monrabal: We collaborated for cal results for intrinsic viscosity, detector to analyze very low levels over two years with recognized CCD measurement, and Xylene of branching in HDPE pipe polyolefin scientists to improve on solubles measurement. resins. what existing data processing software provided. They wanted PE: What about situations where a PE: You worked for many years in to be able to import all detector processor wants to test an occasion - Dow Chemical’s polymer lab signals to provide a single multi- al competing product or resin sam - before starting your own instrument detector GPC response. Ours is ple picked up at a trade show with company. How did that experience the only package that does. Users one of your test instruments? impact your instrument designs? can also implement their own cal - Monrabal: We always provided Monrabal: The GPC systems that culation algorithms if they want test services to resin companies. I used in the past were difficult to to. Our stand-alone IR4 detector Some polymer analytical labs also maintain. They also required han - can also be added to a competing subcontract tests to us. Now that dling dangerous solvents. We GPC instrument with our GPC we have just completed a large tried to design test instruments One data package. new test laboratory in Valencia, that are both reliable and fully we are beginning to offer analyti - automated. We make the only PE: What about processors and cal and test services to processors polyolefin analysis instruments recyclers, who don’t need such too, who can also benefit from the where the user never has to load sophisticated test equipment. Does information. PE: How can processors learn more about polyolefin characterization testing in general? Monrabal: We co-organize the International Conference on Polyolefin Characterization every two years. The next one is in Houston late next year (www.icpc-conference.org) and will include a Short Course in Polyolefins Characterization Techniques. It’s not just for resin companies and universities. It can help processors understand the microstructures of the resins they use and result in downgauging or improving product performance. When Polymer Char recently opened a large new laboratory in Spain, it began to offer resin test services to plastics processors for the first time, a service it had previ - ously provided to resin producers for many years. www.4spe.org | SEPTEMBER 2011 | PLASTICS ENGINEERING | 59.
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