TY - JOUR A1 - Hupp, Vitus A1 - Schartel, Bernhard A1 - Flothmeier, K. A1 - Hartwig, A. T1 - Flame Retarded Adhesive Tapes and Their Influence on the Fire Behavior of Bonded Parts N2 - Pressure-sensitive adhesive tapes are used in automotives, railway vehicles and construction, where flame retardancy is of major importance. This is why industrial applicants often buy, and industrial tape manufacturers often produce, flame-retardant adhesive tapes, advertised for their good flammability characteristics. Yet, how flame-retardant tapes influence the fire behavior of bonded materials is a rather open question. To investigate this issue, three different substrates were bonded, using eight double-sided adhesive tapes containing two different carriers and two different flame retardants. The bonded substrates were compared to their monolithic counterparts in terms of flammability, fire behavior and fire stability. The fire behavior of adhesive tape bonded materials differed significantly from the monolithic substrates. The usage of different adhesive tapes let to different burning behavior of the bonded materials mainly due to different carrier systems. In contrast, the implementation of flame retardant into the adhesive had rather minor or no effect on the burning behavior of the bonded substrates despite their positive effect on the flammability of the free-standing tape. The carrier changed the HRR curve in the cone calorimeter and was able to both, reduce and increase fire hazards. Using the carrier with the better fire performance can lower the fire growth rate by 20%, the peak of heat release rate by 27%, and the maximum average rate of heat emission by 30% in cone calorimeter tests. Overall, the fire behavior of bonded materials is a complex interaction between substrate, adhesive, and carrier, and depends on the fire scenario the materials are exposed to. KW - Pressure-sensitive adhesive tapes KW - Bonded materials KW - Fire behaviour KW - Fire resistance KW - Flame retardant KW - Cone calorimeter PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626006 DO - https://doi.org/10.1007/s10694-024-01637-2 SN - 1572-8099 SN - 0015-2684 VL - 61 IS - 2 SP - 729 EP - 749 PB - Springer Nature AN - OPUS4-62600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - 1 + 1 ≠ 2 – Laminate Materials Meet Flame Retardancy N2 - Main message: Fire tests monitor the specific response of defined test specimens but are used to assess materials’ fire risks. The weakness of this simplification becomes obvious for laminate materials. The talk delivers inspiring food for thought in discussing the fire behaviour of laminates. The fire behaviour must not be expected to be a simple superposition. The design of laminate can generate fire risks as well as give birth to flame retardancy. Introduction Bench-scale fire testing monitors the reaction-to-fire response of well-defined test specimens in certain fire scenarios. Results are often discussed as kind of material properties; indeed, the fire risks of materials are assessed. The weakness of this simplifying concept becomes obvious when it comes to investigating material systems such as all kind of laminate materials. The talk delivers inspiring food for thought sketching the complex and sometimes surprising fire behaviour of laminates. Experimental The polymer analysis, thermal analysis, and investigation of fire behaviour were performed according to the state of the art, mostly in accordance with the ISO standards. We fulfil high quality standards in terms of maintenance, calibration, participation in round robins, and so on. Work steps such as compounding of the materials or injection moulding of test specimen were outsourced or done with partners that have the relevant core competence. The presentation is based on the conclusions and concrete results of projects performed in the group of the author, whose experimental is described in the corresponding scientific papers in detail.[1-3] Results and Discussion Examples show that the fire behaviour of laminates must not be expected to be a simple superposition of the fire behaviour of the individual materials. Indeed, laminate effects can be crucial and influence the flammability relevantly. The design of the laminate can generate fire risks as well as give birth to synergistic flame retardancy. Veneered wood, lacquered products, or foil laminated materials are sketched to illustrate the topic with its potential and challenges. Glued samples consisting of two plates of the same material are discussed to generate some basic understanding as well as to investigate the fire behaviour of glued materials. The impact of the glue line on the burning behaviour of different polymeric materials such as bisphenol A polycarbonate, polymethylmethacrylate, and wood differs remarkably.[2] Further, the role of the glue including but not limited to using flame retarded glues is scrutinized. Making the best out of this understanding we have proposed to concentrate flame retardancy in the top layer.[1, 3] To achieve optimum flame-retardant effect or flame retardancy without disturbing the property profile of the core, flame retardants are strategically concentrated in the surface layer of thermoplastic materials with a laminate structure. Several systems increasing the charring and forming a residual protective layer are identified showing a synergistic effect compared to homogenously flame retarded test specimen. This research presented a promising solution for reducing the use of flame retardants without sacrificing fire performance or mechanical properties, offering significant advantages for industrial applications. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Fire behaviour of laminates KW - Flame retardancy by laminate design PY - 2025 AN - OPUS4-63394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future N2 - MAIN MESSAGE: Sustainability, or in other words, exploiting environmental conservation for the economic welfare and prosperity for all, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends in sustainable flame-retardant polymeric materials. STARTING POINT AND INTRODUCTION: Transforming the plastics industry into a carbon circular economy over the next 30 years requires an immediate revolution entailing the development of cutting-edge materials and the planning of future industrial production plants. Hence, the innovative field of flame-retardant polymeric materials for electrical engineering, construction, or materials used in transportation should lend its strength to drive this challenge. Visionary solutions are proposed to inspire us, while the implementation of economically feasible concepts can take us forward into the future. A critical and structured overview of current trends towards sustainable, flame-retardant polymeric materials is presented, using examples from the literature and by sketching our own projects performed in recent years. RESULTS AND DISCUSSION: This overview of current trends towards producing sustainable, flame-retardant polymeric materials is presented, selecting outstanding and representative examples from the literature and sketching main points of our own projects performed in this field in recent years. The examples are structured along a common theme leading from the use of old and new natural materials with some intrinsic flame retardancy, via flame-retardant biopolymers and biocomposites, to using renewable sources for flame retardants with the objective of exploiting natural sources available as industrial waste streams. Natural flame retardants and adjuvants are highlighted, although the status of most may be assessed as merely motivating our vision. However, some of these visionary approaches such as discussing sustainable flame retardants for poly(limonene carbonate), a polymer synthesised from renewable waste and CO2, or wastewater phosphorus enriched micro algae as a sustainable flame retardant in polylactide are rather innovative when achieving a surprising high technological readiness level or providing a comprehensive solution for several urgent demands at once. Further, there are natural material streams finding their way into polymer mass production as fillers, adjuvants, polymers, or renewable educt sources. Natural substances originating from industrial waste streams open the door to sustainable solutions, because they are often available at low cost and avoid competition for land with farming or virgin forests. Aside from this main topic, remarks will address the recycling of flame-retarded polymeric materials; flame retardant vitrimers are mentioned as potential materials for recyclable thermosets. At the end of the day, only convincing property profiles will prevail both for exploiting renewable sources and circular design, including cost effectiveness, sufficient availability, consistent quality, processibility, mechanical properties, and flame retardancy. However, sustainability must not be merely tolerated as an additional demand, but should instead be recognized as a solution, because sustainability aspires to ensure our economic welfare now and in the future. T2 - Interflam 2025 CY - Royal Holloway, Egham, UK DA - 30.06.2025 KW - Biocomposites KW - Sustainability KW - Renewable KW - Bio wastefibres KW - Circular economy KW - Phosphorus flame retardants PY - 2025 AN - OPUS4-63671 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui Rozo, Maria A1 - Sunder, S. A1 - Inasu, S. A1 - Meinel, Dietmar A1 - Ruckdäschel, H. A1 - Schartel, Bernhard T1 - Weaving Through Fire and Force: Fire Behavior and Fire Stability of Unidirectional, Bidirectional, and Woven Roving Glass-Fiber Composites N2 - This study systematically investigates the transfer of flame retardants (FRs) from epoxy resins to composites. The flame-retardant composites are formulated using bisphenol A diglycidyl ether as the resin and dicyandiamide as the hardener, reinforced with glass fibers (GFs) using various textile architectures: unidirectional (UD), bidirectional (BD), and woven rovings (WR). These composites are evaluated using bench-scale fire stability tests and cone calorimeter experiments to assess critical parameters, including the temperature at failure, time to failure, and fire behavior. Among the tested configurations, UD-GFs demonstrate superior flame retardancy, fire stability, flammability, and mechanical performance, attributed to their higher residue yield, forming a more efficient protective char layer. However, the addition of FRs is limited by their impact on the material's mechanical properties. When the FR content increases to 30 and 50 wt.% of the resin, the composites exhibit a decrease in mechanical performance, adversely affecting both time to failure and temperature at failure. While adding FRs reduces the risk of fire propagation, it does not substantially enhance fire stability or mechanical performance. KW - Fire Resistance KW - Fiber-Reinforced Polymer Composites KW - Fire Stability KW - Glass Fibers KW - Fire Behavior PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631220 SN - 1438-7492 SN - 1439-2054 VL - 310 IS - 5 SP - 2400432 PB - Wiley VHC-Verlag AN - OPUS4-63122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future N2 - Sustainability, or in other words, exploiting resources under the terms of environmental conservation for the economic welfare and prosperity continuously over time, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends and mainly by sketching our own key projects performed in the field of sustainable flame-retardant polymeric materials in the recent years. T2 - Interflam 2025 CY - London, United Kingdom DA - 30.06.2025 KW - Biocomposites KW - Sustainability KW - Renewable KW - Bio wastefibres KW - Fire Behavior PY - 2025 VL - 1 SP - 187 EP - 190 PB - Interscience Communications Ltd AN - OPUS4-63681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dey, R. A1 - Dudziak, Mateusz A1 - Prescher, A. A1 - Kreitsmann, T. A1 - Zhang, K. A1 - Posten, C. A1 - Thomson, C. A1 - Schartel, Bernhard A1 - Ullrich, M. S. A1 - Thomson, L. T1 - Sustainable Flame-Retardant Poly Lactic AcidBiocomposites Reinforced with Polyphosphate-EnrichedMicroalgae: Unlocking the Potential of Hyper-Compensation N2 - This study examines the dual benefits of microalgae cultivation for wastewatertreatment and the enhancement of polylactic acid-based biocomposites. UsingDesmodesmus sp. in a photobioreactor, both batch and continuous operationsachieve total nitrogen (TN) and total phosphorus (TP) removal rates of up to99.9%, maintaining TN and TP levels below 0.02 mg L−1 in the effluent, aligningwith European discharge standards. Continuous cultivation increases biomassproductivity from 0.102 to 0.43 g L−1 day−1 , a 322% improvement over batchoperations. Nutrient starvation followed by reintroduction to nutrient-richwastewater induces hyper-compensation luxury uptake, with P-enrichedcells accumulating 1.33% intracellular P within six hours — 21% higherthan natural accumulation. The results reveal that luxury phosphorus uptakein microalgae follows a triphasic system of uptake and storage, challengingthe previously suggested biphasic model. When incorporated into Poly lacticacid (PLA), the biomass enhances versatility, offering potential replacementof inorganic P in industrial applications, particularly flame retardants.Pyrolysis and cone calorimetry confirm the thermal and fire-retardantbenefits, with a 20% reduction in peak heat release rate and increased charyield. This work highlights microalgae’s role in sustainable biocomposites,supporting wastewater treatment, nutrient recovery, and CO2 sequestration. KW - biocomposites KW - biopolymers KW - Flame-retardant KW - Hyper compensation KW - Phycoremediation KW - Wastewater treatment PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640408 DO - https://doi.org/10.1002/adsu.202500251 SN - 2366-7486 VL - 9 IS - 8 SP - 1 EP - 11 PB - Wiley VHC-Verlag AN - OPUS4-64040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Jan T1 - This is the Way: An Evidence Based Route to Phytic-acid-based Flame Retardant Poly(lactide acid) N2 - Main message: This study provides an evidence-based route to flame retard poly (lactide acid) (PLA) with phytic acid (Phyt)-based flame retardants (FR). Phyt was prepared with lignin (Lig) and expandable graphite (EG). Three amine salts (arginine (Arg), piperazine (Pip), melamine (Mel)) were also synthesized with Phyt. Findings include UL 94 V0 classification, limited oxygen index (LOI) = 43.7 vol% and reduced total heat released (THR), while molecular weight (MW) was not affected. Combinations lead to the most effective FR. Introduction: As demand for biobased polymers increases, biobased FRs remain scarce in the market. With 28 wt.% P, Phyt is promising to be a biobased FR, but Phyt efficiency as a FR needs to be improved. [1] Furthermore, as a strong acid, it esterifies and hydrolysis PLAs backbone. With the combinations proposed in this study, processability and MW in PLA compounds were untouched, while FR performance of Phyt was enhanced. Experimental: Compounds analyzed in this study were: PLA, PLA Lig, PLA EG, PLA PhytLig, PLA PhytEG, PLA Mel, PLA PhytArg, PLA PhytPip, PLA PhytMel, PLA PhytMel Lig and PLA PhytMel EG. Addition of Phyt based FR was 16.7 wt.%, Lig and EG 10wt.%. Compounds were processed with twin screw extrusion, injection molding and hot press. Analysis was done with size exclusion tomography, differential scanning calorimetry (DSC), tensile strength, cone calorimeter, UL 94, LOI and thermogravimetry analysis (TGA) combined with Fourier transformation infrared spectroscopy (FTIR). Residues were analyzed with scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Results and Discussion: To synthesize the FR, Lig and Phyt (solved in water) were mixed and dried. A solid material formed, which was grinded and then compounded with PLA. The same was done with EG. Phyt + Arg/Pip/Mel FR materials were each titrated to a pH of ~4.5, since this pH is known to be least harmful for the PLA backbone. For PhytMel a salt precipitated. PhytPip and PhytArg were dried and a resin-like structure was obtained, which was grinded to a powder. The molar mass distribution of PLA PhytArg (10,000 g/mol – 600,000 g/mol) is similar to PLAs ranging from 15,000 g/mol – 600,000 g/mol. MW distribution from highest to lowest was PLA > PLA PhytArg > PLA PhytMel > PLA PhytMel EG > PLA PhytMel Lig > PLA PhytEG > PLA PhytLig > PLA PhytPip. The reaction between Phyt and Arg/Mel prevents MW decomposition of PLA through a reaction of P acid and NH2 groups. Tensile strength declined to 35.9 MPA for PLA PhytMel and 32.1 MPA for PLA PhytArg, compared to 51.4 MPA for PLA. DSC analysis revealed TG was not affected for the FR compounds: Phyt Lig/EG/Arg/Mel, compared to PLA. PLA PhytMel crystallinity 𝐾∆𝐻𝑐𝑐𝑐𝑐 was 30%, PLA PhytArg crystallinity was 50%, compared to PLA 𝐾∆𝐻𝑐𝑐 was 46%. Melting peaks were not affected in PLA Phyt Arg/Mel. Flammability investigations lead to results of LOI 25.8 vol%/ UL 94 V2 classification in PLA, PLA PhytArg LOI 43.7 vol%/ UL 94 V2, due to strong dripping as a cooling mode of action. [2] PLA PhytMel burned with intumescent char and LOI 38.2 vol%/ UL 94 V2 was measured. Due to strong melt dripping, PLA PhytPip reached UL 94 V0. TGA revealed increased residue for all FR compounds. When materials were combined in PLA PhytMel EG residue was maximized to 19.9 wt.% (600°C, 𝑁𝑁2 atmosphere). FTIR analysis revealed PO and PH stretching vibrations, indicating radical scavenging. Cone calorimeter investigations of PLA, PLA PhytPip and PLA PhytArg lead to a steep incline in HRR to peak heat release rate (pHRR). Values are provided in Table 1. PLA PhytMel containing compounds exhibited prolonged burning and protective layer. PLA PhytLig, PLA PhytEG, PLA Mel (pHRR >1000) were investigated but proved inferior to PLA PhytMel, PLA PhytMel Lig and PLA PhytMel EG. THR was reduced in all Phyt compounds. Intumescence was observed in all compounds except for PLA Lig, PLA PhytLig and PLA PhytMel Lig. PLA PhytMel EG proved as the most effective compound in fire testing with a firm, coherent and intumescent char structure. This study provides an understanding of Phyt as a FR. It systematically improves Phyts effectiveness and processability in PLA. This evidence T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Polylactide acid KW - Intumescence KW - Phosphorous flame retardant KW - Phytic acid PY - 2025 AN - OPUS4-63395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutz von Faserverbundwerkstoffen: Grundlagen und Konzepte N2 - Vor allen Kurz- und Lang-Glasfaser-verstärkte, aber auch Carbonfaser verstärkte Faserverbundwerkstoffe werden in Schienenfahrzeugen eingesetzt. Dabei sind die Brandschutzanforderungen entsprechend EN 45545 zu erfüllen. Der Übersichtsvortrag führt in die Grundlagen des Brandverhaltens und des Flammschutzes von Compositen ein. Anhand von eigenen Arbeiten wird verdeutlicht, dass Flammschutz maßgeschneidert für Composite, die Matrix und für den zu bestehenden Brandtest erforderlich ist. T2 - SKZ Fachtagung Faserverbundwerkstoffe im Schienenfahrzeugbau CY - Merseburg, Germany DA - 14.05.2025 KW - Faserverbundwerkstoffe KW - Composite KW - Flammschutz KW - Brandverhalten PY - 2025 AN - OPUS4-63123 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chacon Castro, Jose P. T1 - Flame Retardant Polylimonen Carbonate: Material Innovation as a Game Changer N2 - Main message: This research seeks to understand and identify the most promising approaches to enhance the flame resistance of poly(limonene carbonate) (PLimC). Furthermore, the goal is to develop a PLimC-based material that incorporates halogen-free flame retardants (FRs) that are not only highly effective but also environmentally sustainable, contributing to the advancement of greener materials for safer use. Introduction The plastic industry depends on fossil-based materials, causing environmental concerns. PLimC, a sustainable polymer derived from limonene and CO₂ [1], offers a promising alternative. Its use in fire safe applications underscores the need to optimize its performance. This study evaluates halogen free FRs to identify and understand the most promising approaches to enhance PLimC’s flame resistance, aiming to improve fire safety and support eco-friendly material development. Experimental: This study has as its main task to conduct experimental evaluations to analyze the thermal properties, flammability, and fire behavior of each system. Pyrolysis, together with the evolved gases of the samples, were analyzed by thermogravimetric analysis coupled with a FTIR spectrometer. The energy content was determined by using a bomb calorimeter. The flammability of the samples was assessed by the reaction to small flame tests such as the UL 94 burning chamber and limiting oxygen index (LOI). The burning behavior in forced flamed conditions was evaluated using the cone calorimeter. Results and Discussion: Thermal properties were first evaluated to gain a deeper understanding of the pure PLimC thermal stability and fire behavior. This analysis builds on PLimC's structural similarity to polycarbonate (PC), due to its carbonate group, and to polyolefins (PO), due to its aliphatic limonene-derived segment, providing insights into optimizing PLimC for sustainable, fire-safe applications. The initial results, which defined our starting point, showed that the LOI of PLimC was 17.2%, very close to that of PO such as polyethylene (PE) and polypropylene (PP) (~18%). In contrast, PC has a higher LOI of ~24%. Additionally, PLimC did not produce any char (0 wt.-%), similar to PO, whereas PC forms char due to its phenolic structures. The effective heat of combustion of PLimC, measured using bomb calorimetry, was determined to be 31.1 MJ/kg. This value is comparable to that of PC (~30 MJ/kg) but significantly lower than PO (~44 MJ/kg). These findings, which demonstrated similarities to both PO and PC, prompted the evaluation of various commercially available FRs at standard market concentrations. Four halogen-free FR systems were chosen for evaluation: 1. mixture of APP (20 wt.-%) + pentaerythritol (10 wt.-%) as an intumescent system [PLimC / APP / Penta], 2. mixture of the phosphorus compound PX200® (16 wt.-%) + PTFE (0.4 wt.-%) as antidripping [PLimC / PhosC / PTFE], 3. metal hydroxide ATH (50 wt.-%) [PLimC / ATH], and the potassium sulfonate salt Bayowet® (0.4 wt.-%) [PLimC / SulfS]. The concentrations were decided according to the standards used in the industry for polyolefins (system 1 and 3), the mixture polycarbonate / ABS (system 2) and polycarbonates (system 4). PLimC has the usual behavior of a non-charring specimen (fast burning and high peak of heat release). ATH proved to be the most effective flame retardant, achieving the biggest reductions in the effective heat of combustion (EHC) and total heat evolved (THE), as demonstrated by cone calorimeter measurements. Additionally, ATH achieved the highest increase in the LOI (17.1% —> 26.0%). With these results, we understood that the FRs commonly used with polyolefins (at concentrations standard in the industry) exhibit similar behavior in terms of flammability and flame retardancy when applied to PLimC. Although ATH has proven to be an effective flame retardant for PLimC, offering a sustainable solution due to its abundance, non-toxicity, and low environmental impact, we aim to explore bio-based flame retardants to further enhance the material’s sustainability. Since phytic acid salts [2] and lignin [3] have demonstrated flame retardant efficacy in polyolefins, we believe these compounds could also perform well in our system. Phytic acid salts are particularly promising due to their high phosphorus content—and in some cases, nitrogen—which promotes char formation and enhances flame retardancy. Lignin’s unique ability to promote charring could significantly improve flame retardancy, due to the fact that PLimC like polyolefins, lacks inherent char formation. By integrating these bio-based flame retardants, we move closer to developing a fully sustainable material that aligns with the Sustainable Development Goals of the United Nations, contributing to a greener and more resilient future. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Poly(limonene carbonate) KW - Sustainability KW - Halogen free flame retardants PY - 2025 AN - OPUS4-63397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sałasińska, K. T1 - Bio-sourced Flame Retardant System for Engineering Plastics N2 - Main message: Intumescent flame retardant degradation products react with the lignocellulose hydroxyl groups by esterification, causing enhanced effectiveness in char formation [1]. The aim of this work is to prepare polyamide 11 with lower flammability by modifying it with a plant-based flame retardant system. An innovation is the thermal modification of plant raw materials to establish bio-sourced flame-retardant systems dedicated to engineering materials. Introduction: Using plant fillers to modify engineering materials raises concerns due to too low thermal stability and problems during processing. However, substances participating in char formation, such as cellulose and lignin, have higher decomposition temperatures than the processing temperature of most engineering plastics. Appropriate preparation of lignocellulosic materials through modification by thermal methods will enable their partial decomposition in controlled conditions and eliminate components with low thermal stability. Results and Discussion: For PA11, the heat release (HRR) curve is characterized by two peaks (Fig.1), with a maximum value at the end of burning. The flame retardant systems caused the curves to flatten, which was especially visible for samples with the highest sunflower husk share. The maximum values of heat release rate (pHRR) for samples with FRs varied from 991 to 626 kW/m2 and were much lower compared to PA11 (2152 kW/m2) and MPP (1234 kW/m2). All samples with FRs ignited much earlier than the reference materials, especially compared to unmodified polymer (Tab.1). The maximum average rate of heat emission (MARHE), used to forecast flame spread, decreased compared to PA11 (maximum by 30%) and slightly to MPP. Decreases were also noted in the case of total heat emission (THE), corresponding to the total heat released at the end of flame combustion. The values range from 112 to 127, and depending on the series, an increase (SH) or decrease (SHT) with the growth of the amount of bio-based components was observed. The reduction in THE follows from incomplete combustion as an effect of char forming or reduced combustion efficiency [2]. Char formation was proved by an increase in the yield of residue , while a slight decrease in the effective heat of combustion (EHC) suggests activity in the gas phase. Smoke emission was assessed by specific extinction area (SEA). The SEA reduction was noted only for the MPP sample, and introducing sunflower husks increased the smoke released. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Bio-sourced flame retardant systems KW - Engineering plastics KW - Cone calorimetry PY - 2025 AN - OPUS4-63398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -