Document Type: Research Paper


1 National Higher School of Electricity and Mechanics Laboratory of Control and Mechanical Characterization of Materials and Structures, Casablanca, Morocco

2 Higher Institute of Maritims Studies, Laboratory of Mechanics ,Casablanca,Morocco.



In this study, the effect of six successive recycling cycles of the recycled material from high impact polystyrene disposable cups on tensile properties, glass transition temperature, flexural, impact strength tests and fluidity were studied. It has been found that after increasing recycling, the molar mass and the viscosity decrease (a slight increase of melt flow index) until the fifth cycle, the maximum yielding stress decreased due to material brittleness .The impact strength has only been relatively influenced by a 17% increase, whereas the elongation at break and the young''s modulus dropped with reprocessing cycles. Glass transition temperature have undergone a remarkable decrease: It dropped in a consistent way, by the sixth cycle we measured a drop of almost 11°C compared to the virgin material, with a notable increase in flexural modulus and hardness. The resulted curves show the reliability of this material to be used after a specific number of processing in several industrial applications.

Graphical Abstract


[1]     Mohammed LAMGHARI, L’économie circulaire, la démarche RSE qui peut sauver l’Afrique. Le magasin des éco-technologies, de l’énergie et de l’environnement, 19, 10-11. (2018, June).


[2]     NASSER DJAMA, Nous voulons créer une véritable industrie du recyclage plastique au Maroc. Usine Nouvelle  (2016, Ocober).


[3]     Scheirs, J.,"Polymer Recycling, Science Technology and Applications ", Wiley Series in Polymer Science, 1st Ed, Chichester: John Wiley & Sons, Ltd. X2. (1998).


[4]     La Mantia, Macromolecular Symposia, 2000, 152, pp.201-210. X3. (2000).


[5]     Murthy, Y.R., Raghavendra, N.M,"Studies on The Degradation of Polystyrene", Pop. Plast. 26(10), pp14-16. X4. (1981).


[6]     Inaba, A, Inoue , H. "The Effect of Operating Condition of PS and Analysis With a Model of The Degradation Process" kagaku kogaku Ronbunshu J.,7(6),pp.602-9. X5. (1981).


[7]     Vilaplana, Francisco, Amparo, Ribes, Karlsson, Sigbritt, Degradation of recycled high-impact polystyrene. Simulation by reprocessing and thermo-oxidation. Polymer Degradation and Stability. 91. 2163-2170. (2006).


[8]     Soriano, Florentino, Morales, Graciela, Díaz de León, Ramón, Recycling of high impact polystyrene in coextruded sheet: Influence of the number of processing cycles on the microstructure and macroscopic properties, Polymer Engineering & Science. Vol. 46, pp. 1698 - 1705. (2006).


[9]     Boldizar, Antal, Moller, Kenneth. Degradation of ABS during repeated processing and accelerated ageing. Polymer Degradation and Stability. 81. 359-366. (2003).


[10]   ISO 294-1:2017, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 1: General principles, and moulding of multipurpose and bar test specimens.


[11]   ISO 294-2:2018, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 2: Small tensile bars.


[12]   ISO 11357-1:2016, Plastics — Differential scanning calorimetry (DSC) — Part 1: General principles.


[13]   Anurag Yadav, Amit Kumar, Pradeep K. Singh & Kamal Sharma, Glass transition temperature of functionalized graphene epoxy composites using molecular dynamics simulation, Integrated Ferroelectrics, 186:1, 106-114, (2018).


[14]   Kumar, A., Sharma, K. & Dixit, A.R. J, Mater Sci, Vol. 54, p. 5992, (2019).


[15]   C. A. Daniels, Polymers: Structure and Properties, 1st ed., Technomic, pp. 18–19, (1985).


[16]   ASTM D1238-13, Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer, ASTM International, West Conshohocken, PA, 2013.


[17]   D. G. Drobny, Handbook of Thermoplastic Elastomers, 2nd ed., William Andrew Publishing, pp. 33–35, (2014).


[18]   John H. Briston, Plastics films, Longman Scientific & Technical, England, pp. 28–29, (1989).


[19]   D. Y. Fung, P. Tong, Classical and Computational Solid Mechanics, 2nd ed., World Scientific publishing, Singapore, pp. 140–143, (2001).


[20]   B.J. Hunt, ‎M.I. James, Polymer  Characterisation, 1st ed., Springer Netherlands, pp. 279–282, (2012).


[21]   Mark E. Tuttle, Structural Analysis of Polymeric Composite Materials, 2nd ed., CRC Press, pp. 12–14, (2012).


[22]   ISO 527-1:2012, Plastics — Determination of tensile properties — Part 1: General principles.


[23]   ISO 178:2010/Amd.1:2013, Plastics — Determination of flexural properties AMENDMENT 1.


[24]   Salmi, H., El Had, K., El Bhilat, H., Hachim, A. ''Numerical Analysis of the Effect of External Circumferential Elliptical Cracks in Transition Thickness Zone of Pressurized Pipes Using XFEM'', Journal of Applied and Computational Mechanics, 5(5), pp. 861-874. (2019). 


[25]   Zadshakoyan, M., Khalilpourazary, S., Hoseini, S. ''Effect of Shear State on Fracture of Refined Grain Pure Copper'', Journal of Computational & Applied Research in Mechanical Engineering (JCARME). (2019).


[26]   Houda, S., Abdeliah, H., El Bhilat, H., El Had, K. ''Numerical modeling and comparison study of elliptical cracks effect on the pipes straight and with thickness transition exposed to internal pressure, using XFEM in elastic behavior.'', Journal of Computational & Applied Research in Mechanical Engineering (JCARME). (2019).  


[27]   Robert F. Landel, ‎Lawrence E. Nielsen, Mechanical Properties of Polymers and Composites, 2nd ed., Marcel Dekker, pp. 315–319, (1993).


[28]   ISO 179-1:2010, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test.


[29]   S.W. Hawley, Physical Testing of Thermoplastics, Pergamon Press, pp. 17–18, (1992).


[30]   A. Alavudeen, ‎N. Venkateshwaran, ‎J. T. Winowlin Jappes, A Textbook of Engineering Materials and Metallurgy, 1st ed, LAXMI Publications, pp. 175–176, (2006).


[31]   NF ISO 48-5 December 2018, T46-003-5, Rubber, vulcanized or thermoplastic - Determination of hardness - Part 5: indentation hardness by IRHD pocket meter method.


[32]   M. Kutz, Applied Plastics Engineering Handbook: Processing and Materials, 1st ed, William Andrew, pp. 213–216, (2006).


[33]   Gottfried W. Ehrenstein, Sonja Pongratz, Resistance and Stability of Polymers, Hanser Publishers, Munich pp 39-51, (2013).


[34]   Scaffaro, R. , La Mantia, F. , Botta, L. , Morreale, M. , Tz. Dintcheva, N. and Mariani, P, Competition between chain scission and branching formation in the processing of high‐density polyethylene: Effect of processing parameters and of stabilizers. Polym Eng Sci, Vol. 49, pp. 1316-1325, (2009).


[35]   D. W. Van Krevelen, K. Te Nijenhuis, Properties of polymers, Elsevier B.V, pp (468-469). (2009).


[36]   A. A. Collyer, Rubber Toughened Engineering Plastics, SPRINGER-SCIENCE+BUSINESS MEDIA, B.V, pp (37-40). (1994).