Chain extension and degradation during reactive processing of PET in the presence of triphenyl phosphite

Polymer Engineering and Science - Tập 47 Số 12 - Trang 2155-2163 - 2007
F.N. Cavalcanti1, Edvânia Trajano Teófilo1, Marcelo S. Rabello1, Suédina Maria de Lima Silva1
1Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, Brazil

Tóm tắt

AbstractPoly(ethylene terephthalate) (PET) is chemically degraded during processing and/or using by a number of sources including temperature, humidity, and ultraviolet radiation. As a consequence, a large loss in engineering properties is observed when PET products are recycled. To overcome this problem, various types of chain extenders were developed in an attempt to recover the polymer molecular sizes by chemical reactions during processing. This work investigates the use of triphenyl phosphite (TPP) as a chain extender of virgin and recycled PET. Compounds with 1 and 3% of TPP were prepared and processed under various conditions using a torque rheometer. An increase in torque during mixing was associated with chain extension reactions whereas the observed decrease in torque afterwards was due to chemical degradation. The optimum processing conditions were reached (260°C, 1% chain extender), with a maximum in chain extension and a minimum in subsequent degradation. An important finding of this work was that the chemical degradation of chain extended PET occurs very easily during storage and it was considered to be a result of the influence of by‐products of TPP reaction with PET. The extraction of these products with acetone was shown to be quite effective, with a considerable stability during storage. This work also showed that the recycled PET is much less able to react with TPP in comparison with the virgin polymer. POLYM. ENG. SCI., 47:2155–2163, 2007. © 2007 Society of Plastics Engineers

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Tài liệu tham khảo

10.1023/A:1021067027612

Fechine G.J.M., 2004, Polymer, 47, 223

10.1002/app.24517

10.1002/app.1972.070160116

10.1002/app.1973.070170622

10.1016/0141-3910(94)90074-4

10.1016/j.eurpolymj.2005.02.005

10.1016/S0032-3861(00)00032-X

10.1002/pola.1986.080240614

10.1002/pen.20155

10.1002/app.1987.070330838

10.1002/app.1985.070300815

10.1515/POLYENG.2001.21.6.543

10.1515/POLYENG.2000.20.2.143

10.1002/app.1993.070500903

10.1002/pen.10760

10.1002/app.1986.070320534

10.1002/app.1986.070320423

10.1016/j.eurpolymj.2005.04.010

10.1016/j.eurpolymj.2005.05.036

10.1002/pi.1526

10.1002/app.23166

S.M.AharoniandD.Masilamani U.S. 4 468 720 (1986).

10.1016/0032-3861(96)80846-9

10.1016/0032-3861(96)00251-0

10.1021/ma946431h

10.1016/S0032-3861(97)00097-9

10.1023/A:1019963923884

10.1021/ac60094a024

10.1007/BF00272226

10.1002/pol.1972.150100412

10.1016/S0141-3910(01)00214-2

10.1016/S0141-3910(98)00094-9