CO intensive carbon black (CB) as filler material in natural rubber-based composites needs to be partially replaced by suitable fillers. In this study, a novel surface modified filler (SuMo FA) was made by encapsulating fly ash (FA) with a polysulphide coating. This SuMo FA was hydrophobic, minimized leaching, and was morphologically ideal as partial replacement filler of CB in rubber-based composites. This SuMO fly ash and unmodified FA was compounded from 5, 10 and 20 parts per hundred rubber (phr) accounting for partial substitution of CB at 5, 10, 20 and 40 (by weight (wt%)), respectively. The tensile properties and Shore A hardness were practically unchanged with unmodified FA at 5 wt% CB replacement. SuMo FA performed better, retaining tensile properties up to 20 wt% CB replacement. Major decreases were seen only at 40 wt% CB replacement. Chemical crosslink densities decreased somewhat with increasing ash content, while thermal stability remained constant. The encapsulation reduced the leachability of toxic heavy metals from SuMo FA to below United States-Environmental Protection Agency limits opening up the use of such composites in consumer markets in addition to industrial ones. Thus, SuMo FA is a promising waste-derived filler that can be used to partially replace carbon black in rubber composites without loss of mechanical properties or thermal stability.

中文翻译：

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使用表面改性粉煤灰减少橡胶碳复合材料的碳足迹


CO密集型炭黑（CB）作为天然橡胶基复合材料中的填充材料，需要用合适的填料部分替代。在这项研究中，通过用聚硫化物涂层封装粉煤灰（FA）制成了一种新型表面改性填料（SuMo FA）。这种 SuMo FA 具有疏水性，可最大限度地减少浸出，并且在形态上非常适合作为橡胶基复合材料中炭黑的部分替代填料。这种SuMO飞灰和未改性的FA由每百份橡胶5份、10份和20份(phr)混合而成，分别以5、10、20和40份(按重量(wt%)计)部分替代CB。未改性 FA 与 5wt% CB 替代物的拉伸性能和肖氏 A 硬度实际上没有变化。 SuMo FA 表现更好，在替代 20wt% CB 时仍保持拉伸性能。仅在 40wt% CB 替代时才出现大幅下降。随着灰分含量的增加，化学交联密度有所下降，而热稳定性保持不变。这种封装将 SuMo FA 中有毒重金属的浸出率降低到美国环境保护署限制以下，从而使此类复合材料在工业市场之外的消费市场中得到使用。因此，SuMo FA 是一种很有前途的废物衍生填料，可用于部分替代橡胶复合材料中的炭黑，而不会损失机械性能或热稳定性。