Calcium hydrogen phosphate dihydrate (DCPD) was evaluated for its potential as a mineral fire retardant (FR) for application in melamine-urea-formaldehyde (MUF)-bonded wood composites. The efficacy as FR was studied in melamine-urea-formaldehyde (MUF)-bonded three-layer particleboard as a function of addition quantities of 10-, 20- and 30 wt%. Resistance to fire and mechanical properties were determined by measuring the self-extinguishing time after flame exposure and internal bond strength, respectively. Combustion behavior was examined on samples with 20 wt% DCPD addition by performing cone calorimetry experiments. The efficacy of DCPD was evaluated by determining the heat release, total heat release rate, smoke production, and smoke production rate and compared to another promising mineral-based fire-retardant composition (FRC) based on hydroxyapatite (HA) with deliquescent salt and HA alone. The effect of FR on the curing behavior of MUF in relation to mechanical properties was determined through viscosity measurements of MUF with 10 wt% addition of FR. The results confirmed the fire-retardant characteristics of DCPD in wood composites, albeit at higher application rates when compared to the FRC, however with no negative impact on resin curing time or mechanical strength. Based on the demonstrated compatibility in MUF, DCPD is considered a promising mineral extender of other FRs for application in UF-based wood composites.

中文翻译：

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评估二水合磷酸氢钙作为矿物基阻燃剂在三聚氰胺-脲醛 (MUF) 粘合木基复合材料中的应用

评估了二水合磷酸氢钙 (DCPD) 作为矿物阻燃剂 (FR) 在三聚氰胺-脲醛 (MUF) 粘合木材复合材料中的应用潜力。在三聚氰胺-脲-甲醛 (MUF) 粘合的三层刨花板上研究了作为 FR 的功效，作为 10、20 和 30 wt% 的添加量的函数。通过分别测量火焰暴露后的自熄时间和内部粘合强度来确定耐火性和机械性能。通过进行锥形量热实验，对添加 20 wt% DCPD 的样品进行燃烧行为检查。DCPD 的功效通过确定热释放、总热释放率、烟雾产生量、和烟雾产生率，并与另一种有前途的基于羟基磷灰石 (HA) 的矿物基阻燃剂组合物 (FRC) 与潮解盐和单独的 HA 进行比较。FR 对与机械性能相关的 MUF 固化行为的影响通过添加 10 wt% FR 的 MUF 的粘度测量来确定。结果证实了 DCPD 在木材复合材料中的阻燃特性，尽管与 FRC 相比应用率更高，但对树脂固化时间或机械强度没有负面影响。基于在 MUF 中已证明的相容性，DCPD 被认为是其他 FR 的有前途的矿物增量剂，可用于 UF 基木材复合材料。FR 对与机械性能相关的 MUF 固化行为的影响通过添加 10 wt% FR 的 MUF 的粘度测量来确定。结果证实了 DCPD 在木材复合材料中的阻燃特性，尽管与 FRC 相比应用率更高，但对树脂固化时间或机械强度没有负面影响。基于在 MUF 中已证明的相容性，DCPD 被认为是其他 FR 的有前途的矿物增量剂，可用于 UF 基木材复合材料。FR 对与机械性能相关的 MUF 固化行为的影响通过添加 10 wt% FR 的 MUF 的粘度测量来确定。结果证实了 DCPD 在木材复合材料中的阻燃特性，尽管与 FRC 相比应用率更高，但对树脂固化时间或机械强度没有负面影响。基于在 MUF 中已证明的相容性，DCPD 被认为是其他 FR 的有前途的矿物增量剂，可用于 UF 基木材复合材料。