{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T20:47:50Z","timestamp":1790023670200,"version":"4.0.1"},"reference-count":57,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,16]],"date-time":"2021-09-16T00:00:00Z","timestamp":1631750400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In this work, conventional sulfur and two types of organic peroxides (dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB)) curing systems were used to investigate the possibility for tailoring of the performance properties of GTR\/NBR blends reinforced with a variable content of highly dispersive silica (0\u201330 phr). The curing characteristics, static mechanical and acoustical properties, swelling behavior, thermal stability, and microstructure of the prepared composites were investigated. The results show that regardless of the curing system used, increasing the content of highly dispersive silica resulted in the improvement of the mechanical properties of the studied materials. It was observed that sulfur-based systems are the best choice in terms of cross-linking efficiency determined based on torque increment and cross-link density parameters. However, further analysis of the physico-mechanical properties indicated that the cross-linking efficiency does not match the performance of specimens, and the materials obtained using organic peroxides show higher tensile properties. This is due to the improved physical interactions between the GTR\/NBR matrix and highly dispersive silica when using peroxide systems. It was confirmed using the analysis of the Wolff activity coefficient, indicating the enhanced synergy.<\/jats:p>","DOI":"10.3390\/ma14185345","type":"journal-article","created":{"date-parts":[[2021,9,18]],"date-time":"2021-09-18T00:13:47Z","timestamp":1631924027000},"page":"5345","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["GTR\/NBR\/Silica Composites Performance Properties as a Function of Curing System: Sulfur versus Peroxides"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5264-6730","authenticated-orcid":false,"given":"\u0141ukasz","family":"Zedler","sequence":"first","affiliation":[{"name":"Department of Polymer Technology, Faculty of Chemistry, Gda\u0144sk University of Technology, Gabriela Narutowicza 11\/12, 80-233 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3511-852X","authenticated-orcid":false,"given":"Xavier","family":"Colom","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Universitat Polit\u00e8cnica de Catalunya Barcelona Tech, Colom 1, Terrassa, 08222 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1502-6962","authenticated-orcid":false,"given":"Javier","family":"Ca\u00f1avate","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Universitat Polit\u00e8cnica de Catalunya Barcelona Tech, Colom 1, Terrassa, 08222 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0867-9794","authenticated-orcid":false,"given":"Krzysztof","family":"Formela","sequence":"additional","affiliation":[{"name":"Department of Polymer Technology, Faculty of Chemistry, Gda\u0144sk University of Technology, Gabriela Narutowicza 11\/12, 80-233 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kole, P.J., L\u00f6hr, A.J., Van Belleghem, F.G.A.J., and Ragas, A.M.J. (2017). Wear and tear of tyres: A stealthy source of microplastics in the environment. Int. J. Environ. Res. Public Health, 14.","DOI":"10.3390\/ijerph14101265"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.resconrec.2018.02.016","article-title":"Recycling of rubber wastes by devulcanization","volume":"133","author":"Asaro","year":"2018","journal-title":"Resour. Conserv. Recycl."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"306","DOI":"10.1016\/j.rser.2016.09.110","article-title":"Energetic valorization of waste tires","volume":"68","author":"Machin","year":"2017","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"909","DOI":"10.1016\/S0079-6700(00)00020-4","article-title":"Reclamation and recycling of waste rubber","volume":"25","author":"Adhikari","year":"2000","journal-title":"Prog. Polym. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"565","DOI":"10.3144\/expresspolymlett.2019.48","article-title":"Microwave treatment in waste rubber recycling\u2014Recent advances and limitations","volume":"13","author":"Formela","year":"2019","journal-title":"Express Polym. Lett."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3099","DOI":"10.1177\/0021998318761554","article-title":"Structural and physico-mechanical properties of natural rubber\/GTR composites devulcanized by microwaves: Influence of GTR source and irradiation time","volume":"52","author":"Colom","year":"2018","journal-title":"J. Compos. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1016\/j.polymertesting.2010.03.010","article-title":"Novel recycled polyethylene\/ground tire rubber\/bitumen blends for use in roofing applications: Thermo-mechanical properties","volume":"29","author":"Navarro","year":"2010","journal-title":"Polym. Test."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/j.cej.2015.03.038","article-title":"Chemically modified ground tire rubber as fluoride ions adsorbents","volume":"282","author":"Rungrodnimitchai","year":"2015","journal-title":"Chem. Eng. J."},{"key":"ref_9","first-page":"1233","article-title":"Dielectric and mechanical characterization of PVC composites with ground tire rubber","volume":"45","author":"Rahhali","year":"2010","journal-title":"J. Compos. Mater."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1061","DOI":"10.1177\/0021998313482154","article-title":"Acoustic and mechanical properties of recycled polyvinyl chloride\/ground tyre rubber composites","volume":"48","author":"Colom","year":"2013","journal-title":"J. Compos. Mater."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1016\/j.matdes.2008.05.065","article-title":"The influence of CB loading on thermal aging resistance of SBR and NBR rubber compounds under different aging temperature","volume":"30","author":"Mostafa","year":"2009","journal-title":"Mater. Des."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1590\/S0104-66322009000100003","article-title":"The use of styrene-butadiene rubber waste as a potential filler in nitrile rubber: Order of addition and size of waste particle","volume":"29","author":"Baeta","year":"2009","journal-title":"Braz. J. Chem. Eng."},{"key":"ref_13","first-page":"412","article-title":"Flame retardancy and foaming properties of the NBR\/ground tire rubber foams containing expandable graphite","volume":"28","author":"Moon","year":"2004","journal-title":"Polymer"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1016\/j.jiec.2007.12.006","article-title":"Halogen-free flame retarding NBR\/GTR foams","volume":"14","author":"Choi","year":"2008","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1118","DOI":"10.1002\/app.30626","article-title":"Improvement of the properties of ground tire rubber (GTR)-filled nitrile rubber vulcanizates through plasma surface modification of GTR powder","volume":"114","author":"Zhang","year":"2009","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_16","first-page":"171","article-title":"Influence of microwave treatment conditions of GTR on physico-mechanical and structural properties of NBR\/NR\/GTR composites","volume":"76","author":"Colom","year":"2019","journal-title":"Afinidad"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1016\/j.polymdegradstab.2017.07.004","article-title":"Processing, physico-mechanical and thermal properties of reclaimed GTR and NBR\/reclaimed GTR blends as function of various additives","volume":"143","author":"Zedler","year":"2017","journal-title":"Polym. Degrad. Stab."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Maciejewska, M., and Siwek, M. (2020). The influence of curing systems on the cure characteristics and physical properties of styrene\u2013butadiene elastomer. Materials, 13.","DOI":"10.3390\/ma13235329"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Kru\u017eel\u00e1k, J., Kvasni\u010d\u00e1kov\u00e1, A., Dosoudil, R., Hudec, I., and Vil\u010d\u00e1kov\u00e1, J. (2020). Combined sulfur and peroxide curing systems applied in cross-linking of rubber magnets. Polym. Polym. Compos.","DOI":"10.1002\/masy.202000258"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Mas\u0142owski, M., Miedzianowska, J., and Strzelec, K. (2019). Natural rubber composites filled with crop residues as an alternative to vulcanizates with common fillers. Polymers, 11.","DOI":"10.3390\/polym11060972"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1016\/j.compositesb.2018.03.024","article-title":"Preparation and characterization of natural rubber composites highly filled with brewers' spent grain\/ground tire rubber hybrid reinforcement","volume":"145","author":"Zedler","year":"2018","journal-title":"Compos. Part B Eng."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1986","DOI":"10.1002\/pen.21126","article-title":"Effect of the filler characteristics on the miscibility of styrene-butadiene rubber and nitrile-butadiene rubber blends","volume":"48","author":"Sierra","year":"2008","journal-title":"Polym. Eng. Sci."},{"key":"ref_23","first-page":"28","article-title":"A key to enhancement of compatibility and dispersion in elastomer blends","volume":"64","author":"Dierkes","year":"2011","journal-title":"Kautsch. Gummi Kunstst."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1016\/j.polymertesting.2018.11.005","article-title":"Towards understanding the role of peroxide initiators on compatibilization efficiency of thermoplastic elastomers highly filled with reclaimed GTR","volume":"73","author":"Hejna","year":"2019","journal-title":"Polym. Test."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Zhao, X., Cornish, K., and Vodovotz, Y. (2019). Synergistic mechanisms underlie the peroxide and coagent improvement of natural-rubber-toughened poly(3-hydroxybutyrate-co-3-hydroxyvalerate) mechanical performance. Polymers, 11.","DOI":"10.3390\/polym11030565"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"4033","DOI":"10.1016\/S0032-3861(97)00539-9","article-title":"Vulcanization of natural rubber modified with cashew nut shell liquid and its phosphorylated derivative\u2014A comparative study","volume":"39","author":"Menon","year":"1998","journal-title":"Polymer"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1545","DOI":"10.1007\/s10973-011-1937-3","article-title":"Vulcanization kinetics study of natural rubber compounds having different formulation variables","volume":"109","author":"Khang","year":"2012","journal-title":"J. Therm. Anal. Calorim."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"512","DOI":"10.1063\/1.1723791","article-title":"Statistical mechanics of cross-linked polymer networks I. rubberlike elasticity","volume":"11","author":"Flory","year":"1943","journal-title":"J. Chem. Phys."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1002\/app.1963.070070306","article-title":"Swelling of filler-reinforced vulcanizates","volume":"7","author":"Kraus","year":"1963","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1016\/j.supflu.2014.06.001","article-title":"Full factorial experimental design to study the devulcanization of ground tire rubber in supercritical carbon dioxide","volume":"92","author":"Mangili","year":"2014","journal-title":"J. Supercrit. Fluids"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1002\/pat.803","article-title":"Biopolymers as fillers for rubber blends","volume":"18","author":"Alexy","year":"2007","journal-title":"Polym. Adv. Technol."},{"key":"ref_32","first-page":"81","article-title":"Effects of silica on the cure properties of some compounds of styrene-butadiene rubber","volume":"9","author":"Ansarifar","year":"2000","journal-title":"Iran. Polym. J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1007\/s10965-017-1293-5","article-title":"The rubber damper reinforced by modified silica fume (mSF) as an alternative reinforcing filler in rubber industry","volume":"24","author":"Suntako","year":"2017","journal-title":"J. Polym. Res."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Maciejewska, M., and Sowi\u0144ska, A. (2021). Influence of fillers and ionic liquids on the crosslinking and performance of natural rubber biocomposites. Polymers, 13.","DOI":"10.3390\/polym13101656"},{"key":"ref_35","first-page":"227","article-title":"Vulcanization kinetics and properties of natural rubber hybrid composites based on maple\/silica\/carbon black","volume":"4","author":"Kazemi","year":"2019","journal-title":"Elastomery"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1515\/polyeng-2014-0034","article-title":"Peroxide vulcanization of natural rubber. Part I: Effect of temperature and peroxide concentration","volume":"34","author":"Hudec","year":"2014","journal-title":"J. Polym. Eng."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1016\/j.polymertesting.2018.03.014","article-title":"Structural, mechanical and thermal behavior assessments of PCL\/PHB blends reactively compatibilized with organic peroxides","volume":"67","author":"Przybysz","year":"2018","journal-title":"Polym. Test."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"31","DOI":"10.5254\/rct.13.87933","article-title":"Comparative investigation of the devulcanization parameters of tire rubbers","volume":"87","author":"Saiwari","year":"2014","journal-title":"Rubber Chem. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.resconrec.2019.01.047","article-title":"Thermo-mechanical devulcanization and recycling of rubber industry waste","volume":"144","author":"Seghar","year":"2019","journal-title":"Resour. Conserv. Recyl."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.wasman.2020.04.032","article-title":"Waste tire rubber as low-cost and environmentally-friendly modifier in thermoset polymers\u2014A review","volume":"108","author":"Hejna","year":"2020","journal-title":"Waste Manag."},{"key":"ref_41","unstructured":"Arastoopour, H., Schocke, D.A., Bernstein, B., and Bilgili, E. (1999). Process for Recycling of Rubber Materials. (U.S. Patent US5904885)."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1177\/1477760618798274","article-title":"A sustainable molding process for new rubber products from tire recycling","volume":"35","author":"Quadrini","year":"2019","journal-title":"Prog. Rubber Plast. Recycl. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/j.polymdegradstab.2015.04.013","article-title":"Influence of process variables on chemical devulcanization of sulfur-cured natural rubber","volume":"118","author":"Sabzekar","year":"2015","journal-title":"Polym. Degrad. Stab."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"109450","DOI":"10.1016\/j.polymdegradstab.2020.109450","article-title":"Assessment of the devulcanization process of EPDM waste from roofing systems by combined thermomechanical\/microwave procedures","volume":"183","author":"Colom","year":"2021","journal-title":"Polym. Degrad. Stab."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"636","DOI":"10.5254\/1.3538699","article-title":"Cure and mechanical behavior of rubber compounds containing ground vulcanizates. Part I: Cure behavior","volume":"67","author":"Gibala","year":"1994","journal-title":"Rubber Chem. Technol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"47957","DOI":"10.1021\/acsami.0c13722","article-title":"Rubber recycling: Mending the interface between ground rubber particles and virgin rubber","volume":"12","author":"Sun","year":"2020","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"857","DOI":"10.5254\/1.3543115","article-title":"Relation of peroxide decomposition to rubber degradation","volume":"24","author":"Kendall","year":"1951","journal-title":"Rubber Chem. Technol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"60","DOI":"10.5254\/rct.16.83758","article-title":"Vulcanization of rubber compounds with peroxide curing systems","volume":"90","author":"Hudec","year":"2017","journal-title":"Rubber Chem. Technol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1007\/s13726-013-0214-7","article-title":"Curing characteristics, mechanical properties and morphology of butyl rubber filled with ground tire rubber (GTR)","volume":"23","author":"Formela","year":"2014","journal-title":"Iran. Polym. J."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1016\/j.wasman.2018.05.054","article-title":"Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect","volume":"78","author":"Song","year":"2018","journal-title":"Waste Manag."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1007\/BF01739290","article-title":"Infrared spectroscopy of carbon-filled polymers","volume":"6","author":"Stevenson","year":"1987","journal-title":"J. Mater. Sci. Lett."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Zedler, \u0141., Colom, X., Ca\u00f1avate, J., Saeb, M.R., Haponiuk, J.T., and Formela, K. (2020). Investigating the impact of curing system on structure-property relationship of natural rubber modified with brewery by-product and ground tire rubber. Polymers, 12.","DOI":"10.3390\/polym12030545"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/S0040-6031(99)00119-7","article-title":"Thermogravimetric analysis of two Chinese used tires","volume":"333","author":"Cui","year":"1999","journal-title":"Thermochim. Acta"},{"key":"ref_54","first-page":"050012","article-title":"Perfect sound insulation property of reclaimed waste tire rubber","volume":"1717","author":"Ubaidillah","year":"2016","journal-title":"AIPC"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/S0142-9418(98)00009-9","article-title":"Acoustic properties of rubber crumbs","volume":"18","author":"Pfretzschner","year":"1999","journal-title":"Polym. Test."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Zhang, H. (2011). Heat-insulating materials and sound-absorbing materials. Build. Mater. Civ. Eng., 304\u2013423.","DOI":"10.1533\/9781845699567.304"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"957","DOI":"10.1002\/app.22379","article-title":"Reinforcing effect of silica on the properties of styrene butadiene rubber\u2013reclaim rubber blend system","volume":"99","author":"De","year":"2006","journal-title":"J. Appl. Polym. Sci."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/14\/18\/5345\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:00:43Z","timestamp":1760166043000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/14\/18\/5345"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9,16]]},"references-count":57,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2021,9]]}},"alternative-id":["ma14185345"],"URL":"https:\/\/doi.org\/10.3390\/ma14185345","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9,16]]}}}