Phenol formaldehyde resin (PFR) has been widely used in many fields, including adhesion, refractory, coating, mold, and foam plastics. However, with the depletion of fossil fuels and more concerns on carbon neutral in recent years, the application of bio-oil to prepare bio-oil formaldehyde resin (BFR) for replacing phenol with bio-oil is arousing great interest, which is beneficial for reducing the carbon emission and the production cost. However, the thermal stability of BFR is far from satisfactory. More flammable and toxic volatile substances will be released from BFR than from PFR, which strongly poses safety and healthy risks to the fabricating workers and the users of the resin. In this work, the thermal stability of BFR is investigated by TG and Py-GC/MS methods, for better understanding the reasons behind the low thermal stability of BFR and for improving the thermal stability of the resin. The content of phenols and the presence of some non-phenolic compounds in bio-oil, as well as the catalyst dosage of NaOH, are studied. It is found that acetic acid has a strong inhibiting role to the reaction. The addition of NaOH can improve the thermal stability, but a large amount of NaOH may reversely promote the release of volatile matters. The separation of acetic acid before polymerization is a better choice than the addition of more NaOH. The reaction is found more complex beyond the factors discussed, so more parameters such as the curing conditions are necessary for further investigations in future work.

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中文翻译：

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TG和Py-GC/MS方法对生物油甲醛树脂热稳定性的因素分析

酚醛树脂（PFR）已广泛应用于粘合、耐火、涂料、模具、泡沫塑料等领域。然而，近年来随着化石燃料的枯竭以及人们对碳中和的关注，应用生物油制备生物油甲醛树脂（BFR）以生物油替代苯酚引起了人们的极大兴趣，这有利于减少碳排放和生产成本。然而，BFR的热稳定性却远不能令人满意。 BFR 比 PFR 释放更多的易燃和有毒挥发性物质，这对制造工人和树脂使用者构成严重的安全和健康风险。本工作通过TG和Py-GC/MS方法研究了BFR的热稳定性，以更好地了解BFR热稳定性低的原因并提高树脂的热稳定性。研究了生物油中酚类物质的含量、部分非酚类化合物的存在以及NaOH催化剂的用量。研究发现乙酸对该反应有较强的抑制作用。 NaOH的添加可以提高热稳定性，但大量的NaOH可能反而会促进挥发物的释放。聚合前分离乙酸是比添加更多NaOH更好的选择。发现该反应比所讨论的因素更加复杂，因此需要更多参数（例如固化条件）以供未来工作中的进一步研究。

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