废弃线路板非金属残渣作填充料对镁质胶凝材料性能的影响-《混凝土与水泥制品》杂志社

废弃线路板非金属残渣作填充料对镁质胶凝材料性能的影响

Influence of Non-metallic Residues of Waste Printed Circuit Board as Filling Material on Performance of Magnesium Oxychloride Ce

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关键词：

废弃线路板；非金属残渣；镁质胶凝材料；水化过程；晶体形貌

Key words：

Waste printed circuit boards; Non-metallic residues; Magnesium oxychloride cement; Hydration process; Crystal morphology

刊期：

２０17年第8期

DOI：

文章编号：

1000-4637（2017）08-87-04

基金项目：

作者：

王祖润，杜中，张永贵，余学飞

单位：

中国建材检验认证集团安徽有限公司，合肥市环境监测站，230051）

摘要

摘要：研究了废弃线路板非金属残渣对镁质胶凝材料的水化过程、抗压强度、镁质胶凝材料晶体形貌的影响，结合扫描电镜对其反应机理进行了分析。结果表明，非金属残渣能抑制镁质胶凝材料的早期水化，使水化放热减缓，早期水化率降低，凝结时间延长；非金属残渣对镁质胶凝材料晶体形貌影响较大，使镁质胶凝材料晶体尺寸明显增大；非金属残渣通过多种途径的作用对镁质胶凝材料产生了缓凝作用。当非金属残渣掺量超过15%时，抗压强度下降较大。

Abstract: The effect of non-metallic residues of waste printed circuit boards on the hydration process, compressive strength, and crystal morphology of magnesium oxychloride cement are investigated. By using the SEM, its retarding mechanism is also studied. The results indicate that the addition of non-metallic residues can lead to the delay in the hydration heat evolution. It can also decrease the hydration ratio at in the early stage and delay the prolong induction period of magnesium oxychloride cement. Non-metallic residues has a major effect on the crystal morphology of magnesium oxychloride cement, it can make the crystal sizes larger. Retardation to magnesium oxychloride cement is caused by a variety of ways with the non-metallic residues. When the content of non-metallic residue is more than 15%, the compressive strength decreases quickly.

结论

（1）非金属残渣对镁质胶凝材料具有一定的缓凝作用，非金属残渣的掺入延长了镁质胶凝材料的凝结时间，并使水化放热速度减缓，在使早期水化率降低的同时，对后期水化率的影响也较小。

（2）镁质胶凝材料晶体形貌在非金属残渣的掺入后发生了较多的改变，且通过电镜图片发现非金属残渣的掺加能明显增加其最终的晶体尺寸。

（3）镁质胶凝材料在非金属残渣的多种途径作用下，可产生缓凝作用，非金属残渣树脂中的一些活性基团，如羟基、羧基等的选择性吸附使晶核的生长被抑制，并使晶核的形成减缓，对镁质胶凝材料的水化产生了一定的妨碍，另外，树脂也对镁质胶凝材料的5·1·8相晶体起到了胶体包裹的作用，抑制了晶核在a轴和b轴方向的生长。

（4）非金属残渣中的玻璃纤维易在镁质胶凝材料晶体水化过程中形成团聚现象，使材料内部产生应力集中区域，造成材料内部的缺陷。当非金属残渣掺量为15%时，这种团聚现象还不是特别明显，形成的孔洞不多，对强度的影响不大，但当掺量超过15%之后，团聚现象变多，形成的孔洞数量变多，导致抗压强度下降明显。

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引用本文

王祖润,杜中,张永贵,等.废弃线路板非金属残渣作填充料对镁质胶凝材料性能的影响[J].混凝土与水泥制品,2017(8):87-90.

WANG Z R, DU Z, ZHANG Y G,et al.Influence of Non-metallic Residues of Waste Printed Circuit Board as Filling Material on Performance of Magnesium Oxychloride Cement[J].China Concrete and Cement Products,2017(8):87-90.

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