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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Mater.</journal-id>
<journal-title>Frontiers in Materials</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Mater.</abbrev-journal-title>
<issn pub-type="epub">2296-8016</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">778652</article-id>
<article-id pub-id-type="doi">10.3389/fmats.2021.778652</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Materials</subject>
<subj-group>
<subject>Editorial</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Editorial: Sustainable Flame Retardants and Polymeric Materials</article-title>
<alt-title alt-title-type="left-running-head">Zhang et&#x20;al.</alt-title>
<alt-title alt-title-type="right-running-head">Editorial: Sustainable Flame Retardant Polymer</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Zhang</surname>
<given-names>Yan</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1046487/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Song</surname>
<given-names>Pingan</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/992783/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Liu</surname>
<given-names>Yun</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1046408/overview"/>
</contrib>
</contrib-group>
<aff id="aff1">
<label>
<sup>1</sup>
</label>Laboratory of Polymer Materials and Engineering, NingboTech University, <addr-line>Ningbo</addr-line>, <country>China</country>
</aff>
<aff id="aff2">
<label>
<sup>2</sup>
</label>Centre for Future Materials, University of Southern Queensland, <addr-line>Springfield Central</addr-line>, <addr-line>QLD</addr-line>, <country>Australia</country>
</aff>
<aff id="aff3">
<label>
<sup>3</sup>
</label>College of Textiles and Clothing, Institute of Functional Textiles and Advanced Materials, National Engineering Research Center for Advanced Fire-Safety Materials D&#x26;A (Shandong), Qingdao University, <addr-line>Qingdao</addr-line>, <country>China</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>
<bold>Edited and reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/141704/overview">Nicola Maria Pugno</ext-link>, University of Trento, Italy</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: Yan Zhang, <email>zhangyan@nit.zju.edu.cn</email>
</corresp>
<fn fn-type="other">
<p>This article was submitted to Polymeric and Composite Materials, a section of the journal Frontiers in Materials</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>18</day>
<month>10</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="collection">
<year>2021</year>
</pub-date>
<volume>8</volume>
<elocation-id>778652</elocation-id>
<history>
<date date-type="received">
<day>17</day>
<month>09</month>
<year>2021</year>
</date>
<date date-type="accepted">
<day>30</day>
<month>09</month>
<year>2021</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2021 Zhang, Song and Liu.</copyright-statement>
<copyright-year>2021</copyright-year>
<copyright-holder>Zhang, Song and Liu</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these&#x20;terms.</p>
</license>
</permissions>
<related-article id="RA1" related-article-type="commentary-article" xlink:href="https://www.frontiersin.org/researchtopic/16056" ext-link-type="uri">Editorial on the Research Topic<article-title>Sustainable Flame Retardants and Polymeric Materials</article-title>
</related-article>
<kwd-group>
<kwd>sustainable</kwd>
<kwd>flame retardant</kwd>
<kwd>recycle and waste</kwd>
<kwd>biomass</kwd>
<kwd>bio-derived additive</kwd>
</kwd-group>
</article-meta>
</front>
<body>
<p>Due to increasing environmental consciousness and the gradual depletion of fossil resources, growing concerns have led to the development of novel routes for the utilization of sustainable resources to produce polymeric materials and other useful chemicals. For example, bio-derived materials from renewable resources like polylactic acid have been recognized as a promising and environmentally friendly alternative to petroleum-based plastics, and waste recycled plastics like poly(ethylene terephalate) can reduce white pollution and make full use of resources. However, most of these sustainable polymeric materials are inflammable, which brings about a potential fire threat and limits their application in practice. It is necessary and urgent to expand their application by improving their fire safety.</p>
<p>This research topic on sustainable flame retardants and polymeric materials aims to feature the latest prospects in sustainable flame-retardant materials. It includes discussion of applying flame retardants into renewable or recycled polymeric materials, and the synthesis and application of new flame retardant additives produced from sustainable chemicals. Different flame retardant mechanisms in the condensed phase or gas phase are covered. The topic of our special issue delivers greener strategies for flame retarding polymeric materials, which is quite attractive for experts and scholars working on sustainable materials science, high-performance polymers, flame retardancy,&#x20;etc.</p>
<p>This series includes five research articles that cover flame retardant polymer materials including polyurethane foam (<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.673906">Zheng et&#x20;al.</ext-link>; <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.712809">Yang and Shao</ext-link>), bamboo material (<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.690603">Lin et&#x20;al.</ext-link>; <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.697732">Lin et&#x20;al.</ext-link>), and poly(butylene succinate) (<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.737749">Wang et&#x20;al.</ext-link>). One review is also included in this series about the application of solid waste in the flame retardant field (<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.712188">Gao et&#x20;al.</ext-link>).</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.673906">Zheng et&#x20;al.</ext-link> synthesized silica aerogel nanoparticles immobilized with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-1-oxide. They were used as a flame retardant to improve thermal stability and fire safety by catalyzing the formation of carbonaceous carbon on the surface of polyurethane&#x20;foams.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.690603">Lin et&#x20;al.</ext-link> treated flammable bamboo slices with melamine (MEL) and phytic acid (PA) using layer-by-layer (LBL) assembly technology to improve its flame retardancy properties. The formation of thermally stable char with excellent thermal resistance performed a vital role in suppressing flame spread and heat release.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.697732">Lin et&#x20;al.</ext-link> presented a green strategy for the improvement of the flame retardancy of bamboo materials through the self-assembly of PA and polyethyleneimine (PEI). The treated bamboo specimen showed an increased fire performance index and decreased CO and CO<sub>2</sub> yields.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.712809">He et&#x20;al.</ext-link> designed a modified ammonium polyphosphate (APP) with a novel phosphorus-containing organosilicon compound (PCOC), which had a greater charring ability and better flame-retardant properties than unmodified APP in as-prepared rigid polyurethane&#x20;foam.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.737749">Wang et&#x20;al.</ext-link> fabricated poly(butylene succinate)/diethylphosphinate (PBS/AlPi) composites. The data show that the use of AlPi endows PBS with an improved flame retardancy without seriously sacrificing other comprehensive performances.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fmats.2021.712188">Gao et&#x20;al.</ext-link> reviewed the recent development of waste flame retardants and their impacts on thermal stability, flame retardancy, and smoke suppression of polymers, followed by representative flame-retardant mechanisms.</p>
<p>In summary, these contributions offer effective green strategies for improving the flame retardancy of materials from both synthetic and natural polymers and offer guidance for the field of sustainable flame retardants and polymeric materials.</p>
</body>
<back>
<sec id="s1">
<title>Author Contributions</title>
<p>All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication. YZ wrote the manuscript; PS and YL revised the manuscript.</p>
</sec>
<sec sec-type="COI-statement" id="s3">
<title>Conflict of Interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="s4" sec-type="disclaimer">
<title>Publisher&#x2019;s Note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
<ack>
<p>We would like to express our sincere gratitude to all authors and reviewers, and to the editorial team of Frontiers in Materials.</p>
</ack>
</back>
</article>