Purpose of Review

Conventional formaldehyde-based adhesives for wood-based composite panels are subject to significant concerns due to their formaldehyde emissions. Over the past decade, the wood adhesive industry has undergone a considerable transformation that is characterized by a major push in bio-adhesive development. Various bio-based materials have been explored to create alternatives to conventional formaldehyde-based adhesives. Moreover, growing interest in circularity has led to increasingly exploiting industrial coproducts and by-products to find innovative solutions.

Recent Findings

Industrial production generates many coproducts that can serve as renewable resources to produce eco-friendly materials. These coproducts offer alternative supply sources for material production without encroaching on food production. Many bio-based compounds or coproducts, such as saccharides, proteins, tannins, and lignocellulosic biomass, can also be used to develop bio-based adhesives. As part of ongoing efforts to reduce formaldehyde emissions, new hardeners and crosslinkers are being developed to replace formaldehyde and bio-scavengers. Other alternatives, such as binderless panels, are also emerging.

Summary

This review focuses on sources of bio-based material derived from by-products of various industries, which have many advantages and disadvantages when incorporated into adhesives. Modification methods to enhance their properties and performance in wood-based panels are also discussed. Additionally, alternatives for developing low-emission or formaldehyde-free adhesives are addressed, including hardeners, bio-scavengers, and binderless options. Finally, the environmental impact of bio-based adhesives compared to that of synthetic alternatives is detailed.

中文翻译：

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用于人造板制造的生物基粘合剂和无甲醛技术的最新进展

 审查目的

用于人造板的传统甲醛基粘合剂由于其甲醛排放而受到严重关注。在过去的十年中，木材粘合剂行业经历了巨大的转变，其特点是生物粘合剂的发展得到了大力推动。人们已经探索了各种生物基材料来创造传统甲醛基粘合剂的替代品。此外，人们对循环性的兴趣日益浓厚，导致人们越来越多地利用工业副产品和副产品来寻找创新的解决方案。

 最近的发现

工业生产产生许多副产品，可以作为可再生资源来生产环保材料。这些副产品为材料生产提供了替代供应来源，而又不影响粮食生产。许多生物基化合物或联产品，例如糖类、蛋白质、单宁和木质纤维素生物质，也可用于开发生物基粘合剂。作为减少甲醛排放持续努力的一部分，正在开发新的硬化剂和交联剂来取代甲醛和生物清除剂。其他替代品，例如无粘合剂面板，也正在出现。

 概括

本综述重点关注来自各个行业副产品的生物基材料来源，将其掺入粘合剂中时具有许多优点和缺点。还讨论了增强人造板特性和性能的改性方法。此外，还讨论了开发低排放或无甲醛粘合剂的替代方案，包括硬化剂、生物清除剂和无粘合剂选项。最后，详细介绍了生物基粘合剂与合成替代品相比对环境的影响。