Polymer Degradation and Stability最新文献_第6页

Stabilization of PE with the natural antioxidant t-resveratrol: Interaction of the primary and the secondary antioxidant 用天然抗氧化剂 t-白藜芦醇稳定聚乙烯：一级和二级抗氧化剂的相互作用

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-19 DOI: 10.1016/j.polymdegradstab.2024.111046

Kata Takács , Miklós Ákos Németh , Tibor Renkecz , Dóra Tátraaljai , Béla Pukánszky

The study focuses on the possibility of using resveratrol, a stilbenoid-type natural antioxidant, as a stabilizer in polyethylene. The experiments were carried out in two stages. First, the efficiency of the natural antioxidant was compared to that of a commercial product, and then polymer properties were determined as a function of additive content. Stabilization efficiency was determined by multiple extrusion experiments. Resveratrol proved a very efficient stabilizer, more efficient than the commercial hindered phenolic antioxidant. Resveratrol provides excellent processing stability and the residual stability of PE containing it is exceptional. Because of its large efficiency, 400–500 ppm additive is sufficient to achieve adequate stability for practice. Resveratrol interacts with the secondary phosphorous stabilizer used in the study, and the effect is antagonistic; resveratrol performs better alone than in combination with PEPQ. Accordingly, this unusual effect must be taken into account during formulation and the construction of the actual additive package. Resveratrol is used in other industries, thus it is available in large quantities and relatively cheap. Besides its advantages, the natural antioxidant has some drawbacks, like its high melting temperature, limited solubility in polyethylene, and strong color of its reaction products. Nevertheless, resveratrol has great potential as a stabilizer in certain products.

这项研究的重点是将白藜芦醇这种类芪类天然抗氧化剂用作聚乙烯稳定剂的可能性。实验分两个阶段进行。首先，将天然抗氧化剂的效率与商用产品的效率进行比较，然后根据添加剂含量确定聚合物特性。通过多次挤压实验确定了稳定效率。结果表明，白藜芦醇是一种非常有效的稳定剂，比商用受阻酚类抗氧化剂更有效。白藜芦醇具有出色的加工稳定性，含有白藜芦醇的聚乙烯的残留稳定性也非常出色。由于白藜芦醇的效率很高，在实际应用中，400-500 ppm 的添加剂就足以达到足够的稳定性。白藜芦醇会与研究中使用的二级磷稳定剂发生作用，而且这种作用是拮抗的；白藜芦醇单独使用的效果要好于与 PEPQ 合用的效果。因此，在配制和构建实际的复合添加剂时，必须考虑到这种不寻常的效应。白藜芦醇在其他行业中也有应用，因此它的用量大，价格相对便宜。除了优点之外，这种天然抗氧化剂也有一些缺点，如熔点高、在聚乙烯中的溶解度有限以及反应产物颜色较深。不过，白藜芦醇作为某些产品的稳定剂具有很大的潜力。

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引用次数: 0

Marine durability of carbon black-filled polychloroprene: Effect of seawater ageing on network, tensile and fatigue properties 填充碳黑的聚氯丁烯的海洋耐久性：海水老化对网络、拉伸和疲劳性能的影响

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-19 DOI: 10.1016/j.polymdegradstab.2024.111045

H. Madeira , P.Y. Le Gac , M. Le Gall , E. Verron

With the development of marine renewable energies, the durability of materials at sea is more than ever a major issue in reducing the risk of failure of offshore devices. In this aggressive environment, elastomers, and in particular polychloroprene (CR), have many applications because of their good damping and fatigue properties. However, these materials are subject to ageing in service, which leads to changes in their mechanical properties. The ageing of these materials in a marine environment has not been extensively studied, despite the need to predict components lifetimes. This paper investigates the mechanical and microstructural consequences of a carbon black-filled CR degradation when exposed to seawater. To this end, swelling, uniaxial tensile and fatigue tests are carried out on materials previously subjected to accelerated ageing in natural seawater. Particular attention is paid to understanding the physico-chemical phenomena involved, and analysing fracture and fatigue properties in relation to those of the macromolecular network.

随着海洋可再生能源的发展，海上材料的耐久性比以往任何时候都更成为降低海上设备故障风险的主要问题。在这种恶劣的环境中，弹性体，尤其是聚氯丁烯（CR），因其良好的阻尼和疲劳性能而得到广泛应用。然而，这些材料在使用过程中会发生老化，导致其机械性能发生变化。尽管需要预测部件的使用寿命，但这些材料在海洋环境中的老化尚未得到广泛研究。本文研究了碳黑填充 CR 在暴露于海水时的机械和微观结构退化后果。为此，对之前在天然海水中进行加速老化的材料进行了膨胀、单轴拉伸和疲劳测试。研究特别关注了解其中涉及的物理化学现象，并分析与大分子网络相关的断裂和疲劳特性。

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引用次数: 0

Phosphorus/boron-containing, flame-retardant polyurethane elastomers with great mechanical, shape-memory, and recycling performances 含磷/硼的阻燃聚氨酯弹性体，具有出色的机械、形状记忆和回收性能

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-19 DOI: 10.1016/j.polymdegradstab.2024.111047

Tiantian Zhang , Siqi Huo , Guofeng Ye , Cheng Wang , Qi Zhang , Yijiao Xue , Pingan Song , Hao Wang , Zhitian Liu

Based on sustainable development strategy and practical application requirement, it is crucial to develop high-strength, recyclable, and flame-retardant polyurethane (PU) elastomers. Hence, a flame-retardant, reprocessable, high-performance polyurethane elastomer (PU-DP 1–7) with dynamic boronic ester bonds and phosphorus-containing groups was well-designed and prepared. The chemical structure of PU-DP 1–7 was confirmed by Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). PU-DP 1–7 shows a transmittance of about 60 % at the wavelength of 900 nm, and phosphorus and boron elements are evenly distributed within its surface, confirming the formation of uniform cross-linking network. The inclusion of phosphorus-and boron-containing groups endows PU-DP 1–7 with a vertical combustion (UL-94) V-0 rating, indicative of desired flame retardancy. In addition, PU-DP 1–7 exhibits a tensile strength of 42.7 MPa and an elongation at break of 616.9 %, with high adhesion strengths towards various substrates due to abundant hydrogen bonds within its network. Furthermore, the dynamic borate ester bonds endow PU-DP 1–7 with superior physical recycling and shape-memory properties. After hot-pressing at 130 °C, the reformed PU-DP 1–7 film shows an 83.6 % recovery efficiency in terms of elongation at break. This work presents an integrated strategy to create flame-retardant, recyclable polyurethane elastomers with great mechanical and shape-memory performances by introducing phosphorus-containing segments and dynamic boronic ester bonds.

基于可持续发展战略和实际应用要求，开发高强度、可回收和阻燃的聚氨酯（PU）弹性体至关重要。因此，我们精心设计并制备了一种具有动态硼酸酯键和含磷基团的阻燃、可再加工的高性能聚氨酯弹性体（PU-DP 1-7）。傅立叶变换红外光谱（FTIR）和 X 射线光电子能谱（XPS）证实了 PU-DP 1-7 的化学结构。在波长为 900 纳米时，PU-DP 1-7 的透射率约为 60%，磷和硼元素在其表面均匀分布，证实形成了均匀的交联网络。含磷和硼基团的加入使 PU-DP 1-7 具有垂直燃烧（UL-94）V-0 等级，表明其具有理想的阻燃性。此外，PU-DP 1-7 的拉伸强度为 42.7 兆帕，断裂伸长率为 616.9%，由于其网络中含有大量氢键，因此对各种基材具有很高的粘附强度。此外，动态硼酸酯键赋予聚氨酯-DP 1-7 优异的物理回收和形状记忆性能。经过 130 °C 热压后，重整后的 PU-DP 1-7 薄膜在断裂伸长率方面显示出 83.6 % 的回收效率。这项研究提出了一种综合策略，通过引入含磷片段和动态硼酸酯键，制造出具有良好机械和形状记忆性能的阻燃、可回收聚氨酯弹性体。

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引用次数: 0

Characterization of the thermomechanical and aging behaviour of PAEK and CF/PAEK composites under long-term high-temperatures PAEK 和 CF/PAEK 复合材料在长期高温条件下的热力学和老化行为表征

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-18 DOI: 10.1016/j.polymdegradstab.2024.111043

Hong-Ru Yang , Dong-Ting Gao , Gang Liu , Chun-Hai Chen , Jia-Nan Yao

The growing use of poly(aryl ether ketone) (PAEK) polymers reinforced with carbon fiber (CF) aims to meet the increasing demand for thermoplastic composites in applications that require excellent mechanical properties and thermal stability at higher temperatures. This study investigated the physicochemical properties of PAEK and CF/PAEK composites under long-term high-temperature exposure (150 °C, 200 °C and 250 °C) for durations of 15, 30, and 45 days, aiming to elucidate the durability mechanisms and enhance understanding of their performance. Specifically, the changes in the flexural properties and dynamic thermo-mechanical properties of the materials were evaluated after long-term high-temperature treatment. The results indicated that both PAEK and CF/PAEK composites possess substantial potential for long-term high-temperature applications, with CF not significantly altering the fundamental high-temperature response of the PAEK matrix. Regarding durability mechanisms, at 150 °C, PAEK's amorphous region undergoes chain reorientation, while temperatures of 200 °C and 250 °C induce significant secondary crystallization, which significantly improved the high-temperature mechanical properties of these materials. Additionally, at temperatures up to 250 °C, shorter linear chain fragments form through oxidative scission in PAEK's amorphous molecular chains. This work not only enriches the existing data on the properties of PAEK and CF/PAEK composites after long-term high-temperature treatment, but also provides further insights into their durability mechanisms.

使用碳纤维（CF）增强的聚（芳基醚酮）（PAEK）聚合物的使用日益增多，其目的是满足热塑性复合材料应用中对机械性能和高温下热稳定性的日益增长的需求。本研究调查了 PAEK 和 CF/PAEK 复合材料在 15 天、30 天和 45 天的长期高温暴露（150 °C、200 °C 和 250 °C）条件下的物理化学特性，旨在阐明其耐久性机理并加深对其性能的理解。具体而言，评估了材料在长期高温处理后的弯曲性能和动态热机械性能的变化。结果表明，PAEK 和 CF/PAEK 复合材料都具有长期高温应用的巨大潜力，其中 CF 不会显著改变 PAEK 基体的基本高温响应。关于耐久性机制，在 150 ℃ 时，PAEK 的无定形区会发生链的重新定向，而在 200 ℃ 和 250 ℃ 时则会引起明显的二次结晶，从而显著改善这些材料的高温机械性能。此外，在高达 250 ℃ 的温度下，PAEK 的无定形分子链会因氧化裂解而形成较短的线性链片段。这项研究不仅丰富了 PAEK 和 CF/PAEK 复合材料经长期高温处理后性能的现有数据，还进一步揭示了其耐久性机理。

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引用次数: 0

Embrittlement induced by oxidation in polyethylene: Role of initial bimodality 聚乙烯氧化引起的脆化：初始双模性的作用

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-17 DOI: 10.1016/j.polymdegradstab.2024.111025

R. Laot , P.-Y. Le Gac , M. Le Gall , M. Broudin , C. Ovalle , L. Laiarinandrasana

High density polyethylene films (200 µm) with an initial bimodal chain length distribution were aged in ovens at 60 °C, 70 °C, and 80 °C. Oxidation effects were characterized at the macromolecular scale to measure the chain length distribution, the amount of crystalline phase, the type of crystallites, and the thickness of the amorphous layer. Additionally, mechanical properties were measured using tensile tests. Regardless of the aging temperature, the same behavior was observed: bimodal chain length distribution became unimodal, the crystallinity ratio increased, the amorphous layer thickness decreased, and the polyethylene became brittle. The embrittlement of the polymer is discussed, and two criteria are proposed: a critical molar mass and a critical amorphous layer thickness. The latter appears to be independent of the initial chain length distribution of the polyethylene.

初始链长分布为双峰的高密度聚乙烯薄膜（200 微米）在 60 ℃、70 ℃ 和 80 ℃ 的烘箱中老化。通过测量链长分布、结晶相的数量、结晶体的类型和无定形层的厚度，对氧化效应进行了大分子表征。此外，还使用拉伸试验测量了机械性能。无论老化温度如何，都观察到了相同的行为：双峰链长分布变为单峰，结晶度比率增加，无定形层厚度减少，聚乙烯变脆。对聚合物的脆性进行了讨论，并提出了两个标准：临界摩尔质量和临界无定形层厚度。后者似乎与聚乙烯的初始链长分布无关。

引用次数: 0

Catalyst-free sustainable epoxy vitrimers with fire safety offered by phosphorus-containing compounds 不含催化剂的可持续环氧玻璃rimers，含磷化合物提供防火安全性

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-16 DOI: 10.1016/j.polymdegradstab.2024.111042

Fubin Luo, Shuguang Yang, Xueyan Yang, Yixin Feng, Bili Lin, Yingbing Zou, Hongzhou Li

In this study, we designed and incorporated a phosphorus-rich compound, DPT, which possesses inherent catalytic properties, into a typically sustainable epoxy vitrimer. This innovative strategy enables the fabrication of flame retarded epoxy vitrimers that require no additional catalysts. DPT was synthesized through a reaction between triethanolamine (TEA) and dibenzyl chlorophosphonate (DPCP). The successful synthesis of DPT is attested to by FTIR and NMR analyses. DPT effectively accelerated the curing process of the epoxy vitrimers, yielding materials with exceptional mechanical strength and inherent self-healing abilities. Notably, the pHRR of epoxy vitrimer incorporated with DPT is reduced to 296.3 kW/m², showing a remarkable 54% reduction compared to that of the epoxy vitrimer catalyzed by conventional catalysts. The THR is also decreased from 84.3 to 42.4 MJ/m². Comprehensive analyses using cone calorimetry and TG-FTIR revealed that DPT effectively inhibits the emission of toxic gases. Crucially, the presence of DPT in the epoxy matrix facilitated the formation of a dense and stable phosphorus-laden carbon layer, which not only enhanced flame retardancy but also imparted exceptional smoke suppression capabilities. These findings underscore the potential of DPT for developing high-performance, catalyst-free, flame-retardant epoxy vitrimers.

在本研究中，我们设计了一种富磷化合物 DPT，并将其融入到一种典型的可持续环氧树脂玻璃rimer 中，该化合物具有固有的催化特性。通过这一创新策略，可以制造出无需额外催化剂的阻燃环氧树脂玻璃rimer。DPT 是通过三乙醇胺 (TEA) 和氯膦酸二苄酯 (DPCP) 反应合成的。傅立叶变换红外光谱和核磁共振分析证明了 DPT 的成功合成。DPT 有效地加速了环氧树脂玻璃体的固化过程，使材料具有优异的机械强度和固有的自愈合能力。值得注意的是，与使用传统催化剂催化的环氧树脂玻璃rimer 相比，加入 DPT 的环氧树脂玻璃rimer 的 pHRR 降低到 296.3 kW/m2，显著降低了 54%。THR 也从 84.3 MJ/m2 降至 42.4 MJ/m2。利用锥形量热仪和 TG-FTIR 进行的综合分析表明，DPT 能有效抑制有毒气体的排放。最重要的是，环氧基质中 DPT 的存在促进了致密稳定的含磷碳层的形成，这不仅增强了阻燃性，还赋予了卓越的烟雾抑制能力。这些发现强调了 DPT 在开发高性能、无催化剂、阻燃环氧玻璃rimers 方面的潜力。

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引用次数: 0

One- and two-step synthesis of paramylon mixed ester derivatives and the substitution effect on mechanical properties and seawater biodegradability 巴龙混合酯衍生物的一步法和两步法合成及其对机械性能和海水生物降解性的影响

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-16 DOI: 10.1016/j.polymdegradstab.2024.111037

Ruiqi Li, Jin Ho Seok, Tadahisa Iwata

Paramylon acetate hexanoate (PaAcHex) with total DS=1.7 was prepared by one- and two-step methods with acetylation and hexanoylation in different order (denoted as AcHex and HexAc) in homogeneous DMAc/LiCl. The distribution of substitution at various ring carbon atoms (C2, C4, and C6) of PaAcHex synthesized by different methods was determined by ¹H NMR spectroscopic analysis. The AcHex mixed esters showed a higher DS of long-chain Hex on C2 and C4 than the other samples. All mixed esters were amorphous and their glass transition temperatures (T_g) were obtained from DMA measurements. PaAcHex with higher DS of hexanoate groups had lower T_g and their melt films showed higher flexibility at the same total DS for all three series of samples. PaAcHex films produced by the two-step (AcHex) method exhibited high toughness even with a low DS of hexanoate groups, whereas those synthesized by the one-step and two-step (HexAc) methods were weak and brittle. Biochemical oxygen demand tests indicated that the mixed esters prepared by the two-step (AcHex) method underwent a two-step degradation process, which may be related to the hexanoate groups on C2 and C4. Short–long chain acylation by the two-step (AcHex) method was found to be the optimal synthesis technique for polysaccharide esters that displayed favorable thermoplasticity and controllable seawater biodegradation behavior. These polysaccharide esters show promise as bioplastic materials.

在均相 DMAc/LiCl 溶液中，采用乙酰化和己酰化不同顺序的一步法和两步法（分别称为 AcHex 和 HexAc）制备了总 DS=1.7 的乙酰己酸帕拉米隆（PaAcHex）。通过 1H NMR 光谱分析确定了不同方法合成的 PaAcHex 在不同环碳原子（C2、C4 和 C6）上的取代分布。与其他样品相比，AcHex 混合酯在 C2 和 C4 上显示出更高的长链 Hex DS。所有混合酯都是无定形的，其玻璃化转变温度（Tg）是通过 DMA 测量得到的。在所有三个系列的样品中，己酸基团含量较高的 PaAcHex 具有较低的 Tg，在总含量相同的情况下，其熔融薄膜显示出更高的柔韧性。采用两步法（AcHex）生产的 PaAcHex 薄膜即使己酸基团含量较低，也表现出较高的韧性，而采用一步法和两步法（HexAc）合成的薄膜则较薄且脆。生化需氧量测试表明，两步法（AcHex）制备的混合酯经历了两步降解过程，这可能与 C2 和 C4 上的己酸基团有关。研究发现，采用两步法（AcHex）进行短长链酰化是合成多糖酯的最佳技术，这些多糖酯具有良好的热塑性和可控的海水生物降解行为。这些多糖酯有望成为生物塑料材料。

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引用次数: 0

Highly efficient flame retardancy and fire spread behavior of rigid polyurethane foams with extremely low content of flame retardant 阻燃剂含量极低的硬质聚氨酯泡沫的高效阻燃性和火灾蔓延行为

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-15 DOI: 10.1016/j.polymdegradstab.2024.111039

Liwen Zheng , Jing Zhan , Jiahui Wang , Zhirong Xu , Xiaowei Mu

In recent years, flame-retardant rigid polyurethane foam (RPUF) has once again captured the scholars’ attention due to the growing the growing demands in the field of building energy efficiency. However, the inherent flammability of RPUF is high and the complexities of its flame-retardant mechanisms remain inadequately understood. In this study, a modified biomass material, amino starch phosphate ester was successfully synthesized which was then combined with expandable graphite (EG) and incorporated into RPUF. The research delved into the optimal ratio and minimal flame-retardant additive required to achieve the stringent UL-94 V-0 rating, while also thoroughly investigating the flame retardancy and thermal properties of the composite system. The findings revealed that with just 6 wt.% of flame retardants, the RPUF achieved the UL-94 V-0 rating, with a 41.1 % reduction in peak heat release rate (pHRR) and a 23.7 % decrease in total heat release (THR). Additionally, it diminishes the flame's size and width, leading to quicker extinction, while also lowering the internal combustion temperature of the polyurethane, thereby delaying both preheating and combustion times. The synergistic interaction between amino starch phosphate ester and EG during combustion results in the formation of a dense, continuous char layer, effectively inhibiting the pyrolysis and combustion of RPUF. This study provides a theoretical foundation for the development of efficient flame-retardant systems for RPUF.

近年来，由于建筑节能领域的需求日益增长，阻燃硬质聚氨酯泡沫（RPUF）再次吸引了学者们的目光。然而，RPUF 本身的易燃性很高，而且人们对其阻燃机制的复杂性仍然了解不足。本研究成功合成了一种改性生物质材料--氨基淀粉磷酸酯，然后将其与可膨胀石墨（EG）结合并加入到 RPUF 中。研究深入探讨了达到严格的 UL-94 V-0 等级所需的最佳比例和最小阻燃添加剂，同时还对复合材料系统的阻燃性能和热性能进行了深入研究。研究结果表明，RPUF 只需 6 wt.%的阻燃剂就能达到 UL-94 V-0 级标准，峰值热释放率（pHRR）降低了 41.1%，总热释放率（THR）降低了 23.7%。此外，它还能减小火焰的大小和宽度，使火焰更快熄灭，同时降低聚氨酯的内部燃烧温度，从而延迟预热和燃烧时间。在燃烧过程中，氨基淀粉磷酸酯和 EG 之间的协同作用会形成致密、连续的炭层，从而有效抑制 RPUF 的热解和燃烧。这项研究为开发用于 RPUF 的高效阻燃系统提供了理论基础。

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引用次数: 0

Re-examination of the intumescence mechanism of fire retarded PP with APP/pentaerythritol/zeolite-4A using advanced spectroscopic techniques 利用先进的光谱技术重新研究含有 APP/季戊四醇/zeolite-4A的阻燃聚丙烯的膨胀机理

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-15 DOI: 10.1016/j.polymdegradstab.2024.111040

Matthieu Caron , Karima Ben Tayeb , Serge Bourbigot , Gaëlle Fontaine

The mixture of ammonium polyphosphate (APP) and pentaerythritol (PER) is a very efficient flame retardant (FR) intumescent system suitable for polyolefins such as polypropylene (PP). The mechanisms of intumescence of this FR system in this polymer was investigated using different spectroscopic techniques including continuous wave (CW) electron paramagnetic resonance (EPR) spectroscopy and solid state nuclear magnetic resonance (NMR) technique. In this work, the intumescence mechanism of PP/APP/PER formulations with and without 4A is revisited. The intumescent system was in-depth investigated using NMR, CW EPR and pulsed EPR. The CW EPR technique confirmed that free radicals are mainly generated during the intumescence of the system between 250 and 350 °C. Thanks to the pulsed EPR and solid state NMR, it was evidenced that a key structural shift from a predominantly carbonaceous residue to a predominantly phosphorated residue. Besides, it was also evidenced that zeolite 4A totally collapses during extrusion of PP/APP/PER formulations reacting with APP to generate aluminophosphates. Then, silicophosphates are generated between 350 and 400 °C. Both alumino- and silicophosphates contribute to protect aromatic structures in the residue at high temperatures.

聚磷酸铵（APP）和季戊四醇（PER）的混合物是一种非常高效的阻燃（FR）膨胀体系，适用于聚丙烯（PP）等聚烯烃。研究人员利用不同的光谱技术，包括连续波（CW）电子顺磁共振（EPR）光谱和固态核磁共振（NMR）技术，对这种聚合物中的阻燃体系的膨胀机理进行了研究。本研究重新探讨了含有和不含 4A 的 PP/APP/PER 配方的膨胀机理。使用 NMR、CW EPR 和脉冲 EPR 对膨胀体系进行了深入研究。CW EPR 技术证实，该体系在 250 至 350 °C 的膨胀过程中主要产生自由基。通过脉冲 EPR 和固态 NMR，证明了从以碳质残留物为主到以磷化残留物为主的关键结构转变。此外，还证明沸石 4A 在挤压 PP/APP/PER 配方时会完全塌陷，与 APP 发生反应生成铝磷酸盐。然后在 350 至 400 °C 之间生成硅磷酸盐。在高温条件下，铝磷酸盐和硅磷酸盐都有助于保护残留物中的芳香族结构。

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引用次数: 0

Co Hybrids modified piperazine pyrophosphate towards efficient flame retardancy, smoke suppression, and high mechanical properties of styrenic thermoplastic elastomer Co Hybrids 改性哌嗪焦磷酸盐，实现苯乙烯热塑性弹性体的高效阻燃、抑烟和高机械性能

IF 6.3 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2024-10-15 DOI: 10.1016/j.polymdegradstab.2024.111041

Quanqing Cui , Hongliang Ding , Na Sun , Xiaowei Mu , Wei Wang , Yan Zhang , Keqing Zhou , Wei Yang , Bin Yu

The highly flammable nature of thermoplastic elastomers (TPE) results in poor fire safety performance. The large addition of flame retardants leads to a significant decrease in mechanical properties. To solve above challenges, we design a multilayer core-shell flame retardant, piperazine pyrophosphate@ tannic acid@ Co amorphous hybrids (PAPP@TA@Co-2-MIM) and add it to TPE to enhance the fire safety and mechanical performance simultaneously. It was found that the addition of 32 wt% PAPP@TA@Co-2-MIM achieved a UL-94 V-0 rating of TPE composites, with a limiting oxygen index of 27 %. Compared to pure TPE, the peak heat release rate, total heat release, total smoke production, and peak CO release rate of TPE/PAPP@TA@Co-2-MIM were reduced by 79.8 %, 37.1 %, 42.9 %, and 82.5 %, respectively, effectively suppressing the release of heat, smoke, and toxic gases. Besides, the flame-retardant mechanism was also explained. In terms of mechanical performance, benefiting by the bridging effect of the core-shell structure, the tensile strength of TPE/PAPP@TA@Co-2-MIM increased by 52.7 %, compared to TPE/PAPP. This study designed a TPE composite material that showed good thermal stability, high fire safety performance and enhanced mechanical properties.

热塑性弹性体（TPE）的高易燃性导致其防火安全性能较差。阻燃剂的大量添加会导致机械性能显著下降。为解决上述难题，我们设计了一种多层核壳阻燃剂--焦磷酸哌嗪@单宁酸@Co无定形杂化物（PAPP@TA@Co-2-MIM），并将其添加到热塑性弹性体中，以同时提高防火安全性和机械性能。研究发现，添加 32 wt% PAPP@TA@Co-2-MIM 的 TPE 复合材料达到了 UL-94 V-0 等级，极限氧指数为 27%。与纯 TPE 相比，TPE/PAPP@TA@Co-2-MIM 的峰值热释放率、总热释放率、总烟雾产生量和峰值 CO 释放率分别降低了 79.8%、37.1%、42.9% 和 82.5%，有效抑制了热量、烟雾和有毒气体的释放。此外，还解释了阻燃机理。在机械性能方面，得益于核壳结构的架桥效应，TPE/PAPP@TA@Co-2-MIM 的拉伸强度比 TPE/PAPP 提高了 52.7%。本研究设计的 TPE 复合材料具有良好的热稳定性、较高的防火安全性能和更强的机械性能。

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引用次数: 0