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Licensed Unlicensed Requires Authentication Published by De Gruyter May 10, 2022

Effect of expansion temperature on the properties of expanded graphite and modified linear low density polyethylene

Xiuyan Pang, Wenyu Zhang, Yafang Meng, Meifang Ma and Jianzhong Xu


To study the influence of expansion temperature on the properties of expanded graphite (EBG), EBG300, EBG600, and EBG900 were prepared by heating expandable graphite (EG) at 300, 600, and 900 °C, respectively. Furthermore, the influence of these EBGs on the combustion performance and physical-mechanical properties of linear low density polyethylene (LLDPE) were investigated. The expansion volumes of EBG300, EBG600, and EBG900 increase with the rise of temperature, and a four-stage ordered structure of “graphite worm” gradually forms. The thermal stability increases gradually for EBG300, EBG600, and EBG900. On the contrary, the thermal conductivity decreases in sequence. However, the incorporation of EBG900 promotes the formation of a continuous network structure and makes the modified LLDPE to present the best heat transmission. The addition of 30 wt% of these EBGs significantly improves LLDPE’s flame retardancy and high-temperature thermal stability. The total heat release, the peak value of heat release rate, and the fire growth index of 70LLDPE/30EBG300 reduce by 69, 91, and 87% respectively, while the effective fire performance index improves seven times. The addition of these additives reduces the tensile strength and elongation at break, the larger the EBG size, the more obvious the effect.

Corresponding author: Xiuyan Pang, College of Chemistry and Environmental Science, Hebei University, Wusi East Road No. 180, Baoding, 071002, P. R. China; and Flame Retardant Material and Processing Technology Engineering Technology Research Center of Hebei Province; Key Laboratory of Analytical Science and Technology of Hebei Province, Hebei University, Baoding, P. R. China, E-mail:

Funding source: Natural Science Foundation of Hebei Province

Award Identifier / Grant number: B2015201028

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This study was supported by project (No. B2015201028) of Natural Science Foundation of Hebei Province, P R China. We gratefully acknowledge the support.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.


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Received: 2022-01-04
Accepted: 2022-04-11
Published Online: 2022-05-10
Published in Print: 2022-07-26

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