State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
Water Res. 2018 Sep 15;141:86-95. doi: 10.1016/j.watres.2018.04.021. Epub 2018 Apr 9.
The development of phosphorus-free and biodegradable scale inhibitors has been paid considerable attention. Two series of starch-graft-poly(acrylic acid) (St-g-PAA) samples with different grafting ratios and grafted-chain distributions, that is, the number and length of grafted PAA chains on the starch backbone, were designed and prepared in this study. Fourier transform infrared and H nuclear magnetic resonance spectra were used to further characterize the molecular structures of the St-g-PAAs. In addition to dose, the effects of the structural morphologies of St-g-PAA, namely, grafting ratio and grafted-chain distribution, on the scale-inhibition performance against calcium carbonate were investigated systematically. Structural morphology significantly influenced the scale-inhibition performance of St-g-PAA. St-g-PAA with relatively low grafting ratio (≤97%) displayed better scale-inhibition effect than samples with similar grafted-chain distributions. Meanwhile, under the similar grafting ratios, samples with higher number of branched chains with shorter grafted chains displayed better antiscaling performance. Thus, higher scale-inhibition rate and lower corresponding optimal dose were obtained. Different scale-inhibition mechanisms were involved in the effects of the structural morphology. These mechanisms were investigated in detail from the molecular levels using scanning electron microscopy and X-ray diffraction.
无磷可生物降解阻垢剂的开发受到了相当多的关注。本研究设计并制备了两系列具有不同接枝率和接枝链分布的淀粉接枝聚丙烯酸（St-g-PAA）样品，即淀粉主链上接枝 PAA 链的数量和长度。傅里叶变换红外和 H 核磁共振谱进一步表征了 St-g-PAAs 的分子结构。除了剂量外，St-g-PAA 的结构形态，即接枝率和接枝链分布，对碳酸钙阻垢性能的影响也得到了系统的研究。结构形态显著影响了 St-g-PAA 的阻垢性能。接枝率较低（≤97%）的 St-g-PAA 比具有相似接枝链分布的样品具有更好的阻垢效果。同时，在相似的接枝率下，具有较高支化链数和较短接枝链的样品表现出更好的阻垢性能。因此，获得了更高的阻垢率和更低的相应最佳剂量。结构形态的影响涉及不同的阻垢机制。这些机制从分子水平使用扫描电子显微镜和 X 射线衍射进行了详细研究。
