Investigation of Effects of a Polymeric Chain Extender on the Properties of Recycled Poly (Butylene Terephthalate)

Öz

Poly (butylene terephthalate) (PBT) is one of the most used polyesters today; however, the attempts to convert PBT wastes into value-added products are still limited in the recycling context. One of the major drawbacks of the PBT recycling is thermal degradation during multiple melt processing cycles that leads to deterioration in molecular weight and properties of the polymer. In this study, recycled PBT (rPBT) was compounded with a polymeric chain extender (Joncryl ADR 4368) at different loadings (0.5, 1, 1.5 wt%) in a twin-screw extruder. The rheological, mechanical, and thermal properties of the samples were investigated using different characterization techniques. The rheological results showed that addition of chain extender improved the viscoelastic properties of rPBT due to recoupling of the broken chains. The profound effect of chain extender on upgrading properties of rPBT was also confirmed by tensile test results. The samples containing chain extender showed enhancement in elastic modulus and tensile strength, whereas the strain at break values decreased due to chain branching. The samples containing chain extender showed enhancement in elastic modulus and tensile strength, whereas the strain at break values decreased due to chain branching. The effect of chain extender on branched structure of the samples was also observed from the lower crystallinity values. Thermogravimetric analysis indicated that the chain extender increased thermal decomposition temperature of the PBT. The improvement in the properties of the samples containing chain extender became more significant with increase in chain extender concentration.

Anahtar Kelimeler

• Poly(butylene terephthalate)
• Recycling
• Thermal Degradation
• Chain Extender
• Extruder

Polimerik Bir Zincir Uzatıcının Geri Dönüştürülmüş Poli(Bütilen Tereftalat)’ın Özelliklerine Etkilerinin İncelenmesi

Öz

Poli(bütilen tereftalat) (PBT) günümüzde en fazla kullanılan poliesterlerdendir, ancak PBT atıkların geri dönüşüm kapsamında katma değerli ürünlere dönüşmesine yönelik girişimler hala sınırlıdır. PBT geri dönüşümünün en önemli zorluklarından birisi çoklu eriyik işleme döngüleri sırasındaki termal bozunma olup, polimerin molekül ağırlığı ve özelliklerinde kayıplara yol açmaktadır. Bu çalışmada geri dönüştürülmüş PBT (Gd. PBT) farklı yükleme oranındaki (%ağ. 0.5, 1, 1.5) polimerik bir zincir uzatıcı (Joncryl ADR 4368) ile çift vidalı ekstrüderde harmanlanmıştır. Örneklerin reolojik, mekanik ve termal özellikleri farklı karakterizasyon yöntemleri ile incelenmiştir. Reolojik sonuçlar zincir uzatıcının eklenmesiyle kopan zincirlerin tekrar bağlanarak Gd. PBT’nin viskoelastik özelliklerinin geliştiğini göstermiştir. Zincir uzatıcının Gd. PBT’nin özelliklerine olan önemli etkisi çekme testi sonuçlarından da doğrulanmıştır. Zincir uzatıcı içeren örneklerin elastik modül ve çekme dayanımları artış gösterirken, kopmadaki uzama değerleri zincir dallanmasına bağlı olarak düşmüştür. Zincir uzatıcının örneklerin dallanmış yapısına etkisi düşük kristalinite değerlerinden de gözlemlenmiştir. Termogravimetrik analiz zincir uzatıcının Gd. PBT’nin termal bozunma sıcaklığını arttırdığını göstermiştir. Zincir uzatıcı içeren örneklerin özelliklerindeki iyileşme artan zincir uzatıcı konsantrasyonu ile daha belirgin olmuştur.

Anahtar Kelimeler

• Poli(bütilen tereftalat)
• Geri Dönüşüm
• Termal Bozunma
• Zincir Uzatıcı
• Ekstrüder

Kaynakça

1. D’Ambrieres, W. (2019). Plastics Recycling Worldwide: Current overview and desirable changes. Field Actions Science Reports, 19,12-21.
2. Singh, N., Hui, D., Singh, R., Ahuja, I. P. S., Fea, L., & Fraternali, F. (2017). Recycling of plastic solid waste: A state of art review and future applications. Composites Part B, 115, 409-422.
3. Ragaert, K., Delva, L., & Van Geem, K. (2017). Mechanical and chemical recycling of solid plastic waste. Waste Management, 6, 24-58.
4. Quispe, N. B., Fernandes, E.G., Zanata, F., Bartoli, J. R., Souza, D. H. S., & Ito, E. N. (2015). Organoclay nanocomposites of post-industrial waste poly (butylene terephthalate) from automotive parts. Waste Managementand Research, 33(10), 908-918.
5. Knappich, F., Hartl, F., Schlummer, M., & Maurer, A. (2017). Complete recycling of composite material comprising polybutylene terephthalate and copper. Recycling, 2(9), 1-12.
6. Meng, C., & Qu, J. (2018). Mechanical and thermal properties of poly (butylene terephthalate)/ethylene-vinyl acetate blends using vane extruder. e-Polymers,18(1), 67-73.
7. Da Silva, A. M. G., Barcelos, K. A., Da Silva, M. C., & Morelli, C. L. (2020). Blend of recycled poly (ethylene terephthalate) and polycarbonate with polyaniline for antistatic packaging. Polymers and Polymer Composites, 28(5), 331-337.
8. Martinez, A. L. C., Barrera, G. M., Diaz, C. E. B., Cordoba, L. I. A., Nunez, F. U., & Hernandez, D. J. D. (2019). Recycled polycarbonate from electronic waste and its use in concrete: Effect of irradiation. Construction and Building Materials, 201,778-785.

9. Buccella, M., Dorigato, A., Pasqualini, E., Caldara, M., & Fambri, L. (2014). Chain extension behavior and thermo-mechanical properties of polyamide 6 chemically modified with 1,1-carbonyl-bis-caprolactam. Polymer Engineering and Science, 54(1), 158–165.
10. Passalacqua, V., Pilati, F., Zamboni, V., Fortunato, B., & Manaresi, P. (1976). Thermal degradation of poly(butylene terephthalate). Polymer, 17, 1044-1048.
11. Tuna, B., & Benkreira, H. (2019). Reactive extrusion of polyamide 6 using a novel chain extender. Polymer Engineering and Science, 59(S2), 25-31.
12. Awaja, F., & Pavel, D. (2005). Recycling of PET. European Polymer Journal, 41(7), 1453-1477.
13. Villalobos, M., Awojulu, A., Greeley, T., Turco, G., & Deeter, G. (2006). Oligomeric chain extenders for economic reprocessing and recycling of condensation plastics. Energy, 31(15), 3227–3234.
14. Daver, F., Gupta, R.A., & Kosior, E.N. (2008). Rheological characterisation of recycled poly(ethylene terephthalate) modified by reactive extrusion. Journal of Materials Processing Technology,204, 397-402.
15. Makkam, S., & Harnnarongchai, W. (2014). Rheological and mechanical properties of recycled PET modified by reactive extrusion. Energy Procedia, 56, 547-553.
16. Snowdon, M. R., Abdelwahab, M., Mohanty, A. K., & Misra, M. (2020). Mechanical optimization of virgin and recycled poly(ethylene terephthalate) biocomposites with sustainable biocarbon through a factorial design. Results in Materials, 5, 1-10.
17. Zhao, Z., Wu, Y., Wang, K., Xia, Y., Gao, H., Luo, K., Cao, Z., & Qi, J. (2020). Effect of the trifunctional chain extender on intrinsic viscosity, crystallization behavior, and mechanical properties of poly(ethylene terephthalate). ACS Omega, 5(30), 19247-19254.
18. Xiao, L., Wang, H., Qian, Q., Jiang, X., Liu, X., Huang, B., & Chen, Q. (2012). Molecular and structural analysis of epoxide-modified recycled poly(ethylene terephthalate) from rheological data. Polymer Engineering and Science, 52(10), 2127-2133.
19. Tavares, A. A., Silva, D. F. A., Lima, P. S., Andrade, D. L. A. C. S., Silva, S. M. L., & Canedo, E. L. (2016). Chain extension of virgin and recycled polyethylene terephthalate. Polymer Testing, 50, 26-32.
20. Haralabakopoulos, A. A., Tsiourvas, D., & Paleos, C. M. (1998). Chain extension of poly(ethylene terephthalate) by reactive blending using diepoxides. Journal of Applied Polymer Science, 71(13), 2121-2127.
21. Incarnato, L., Scarfato, P., Maio, L. D., & Acierno, D. (2000). Structure and rheology of recycled PET modified by reactive extrusion. Polymer, 41(18), 6825-6831.
22. Awaja, F., Daver, F., & Kosior, E. N. (2004). Recycled poly(ethylene terephthalate) chain extension by a reactive extrusion process. Polymer Engineering and Science, 44(8), 1579-1587.
23. Daver, F., Gupta, R. A., & Kosior, E. N. (2008). Rheological characterisation of recycled poly(ethylene terephthalate) modified by reactive extrusion. Journal of Materials Processing Technology, 204, 397-402.
24. Tuna, B., & Ozkoc, G. (2017). Effects of diisocyanate and polymeric epoxidized chain extenders on the properties of recycled poly (lactic acid). Journal of Polymers and the Environment, 25(4), 983-993.
25. Beltran, F. R., Infante, C., Orden, M. U., & Urreaga, J. M. (2019). Mechanical recycling of poly(lactic acid): Evaluation of a chain extender and a peroxide as additives for upgrading the recycled plastic. Journal of Cleaner Production, 219, 46-56.
26. Casate de Andrade, M. F., Fonseca, G., Morales, A. R., & Mei, L. H. I. (2018). Mechanical recycling simulation of polylactide using a chain extender. Advanced Polymer Technology, 37, 2053-2060.
27. Standau, T., Hadelt, B., Schreier, P., & Altstadt, V. (2018). Development of a bead foam from an engineering polymer with addition of chain extender: Expanded polybutylene terephthalate. Industrial & Engineering Chemistry Research, 57(50), 17170-17176.
28. Nofar, M., & Oğuz, H. (2019). Development of PBT/recycled PET blends and the influence of using chain extender. Journal of Polymers and the Environment, 27, 1404-1417.
29. Raffa, P., Coltelli, M. B., & Castelvetro, V. (2014). Expanding the application field of post-consumer poly(ethylene terephthalate) through structural modification by reactive blending. Journal of Applied Polymer Science, 131(19), 1-11.
30. Japon, S., Boogh, L., Leterrier, Y., & Manson, J. A. E. (2000). Reactive processing of poly(ethylene terephthalate) modified with multifunctional epoxy-based additives. Polymer, 41(15), 5809-5818.
31. Nguyen, Q. T., Japon, S., Luciani, A., Leterrier, Y., & Manson, J. A. E. (2001). Molecular characterization and rheological properties of modified poly(ethylene terephthalate) obtained by reactive extrusion. Polymer Engineering and Science, 41(8), 1299-1309.
32. Corre, Y. M., Duchet, J., Reignier, J., & Maazouz, A. (2011). Melt strengthening of poly(lactic acid) through reactive extrusion with epoxy-functionalized chains. Rheologica Acta, 50, 613-629.
33. Al-Itry, R., Lamnawar, K., & Maazouz, A. (2012). Improvement of thermal stability, rheological and mechanical properties of PLA, PBAT and their blends by reactive extrusion with functionalized epoxy. Polymer Degradation and Stability, 97, 1898-1914.
34. Tuna, B., & Benkreira, H. (2019). Chain extension of polyamide 6/organoclay nanocomposites. Polymer Engineering and Science, 59(6), 1233-1241.
35. Samperi, F., Puglisi, C., Alicata, R., & Montaudo, G. (2004). Thermal degradation of poly(butylene terephthalate) at the processing temperature. Polymer Degradation and Stability, 83, 11–17.
36. Khankrua, R., Pivsa-Art, S., Hiroyuki, H., & Suttiruengwong, S. (2014). Effect of chain extenders on thermal and mechanical properties of poly(lactic acid) at high processing temperatures: Potential application in PLA/Polyamide 6 blend. Polymer Degradation and Stability, 108, 232-240.
37. Li, H., & Huneault, M. A. (2011). Effect of chain extension on the properties of PLA/TPS blends. Journal of Applied Polymer Science, 122(1), 134-141.
38. Tuna, B., & Benkreira, H. (2018). Chain extension of recycled PA6. Polymer Engineering and Science, 58(7), 1037-1042.