Alipoormazandarani Niloofar, Fokkink Remco, Fatehi Pedram
Chemical Engineering Department, Lakehead University Thunder Bay Canada
Laboratory of Physical Chemistry and Soft Matter, Wageningen University & Research The Netherlands.
RSC Adv. 2021 May 7;11(28):16980-16988. doi: 10.1039/d1ra02248b. eCollection 2021 May 6.
The deposition behavior of lignin on a solid surface was studied using stagnation point adsorption reflectometry (SPAR) comprehensively. In this study, the light absorption coefficient of lignin ( = 20 476 m) at 633 nm wavelength was considered to define a new imaginary refractive index () used in the SPAR technique for adsorption analysis. The inclusion of in the adsorption model yielded an adsorbed amount () of 1.11 mg m, leading to the quality factor ( ) of 31.71 mg m. At a lower concentration, the deposition of lignin on the surface was increased, and it generated a maximum sticking coefficient of = 0.71 at 25 mg L on the surface. At the concentration range of 35 and 45 mg L, lignin formed clusters and its deposition dropped. The use of Quartz crystal microbalance (QCM) and SPAR techniques also confirmed that the proportion of water in the deposited lignin adlayer was greater when a lower concentration (5-25 mg L) of lignin solution was used for adsorption. The findings of this study revealed the potential use of the SPAR technique for evaluating the deposition performance of lignin-based materials on varied surfaces, which would facilitate the development of coating and composite applications for lignin.
采用驻点吸附反射测量法（SPAR）全面研究了木质素在固体表面的沉积行为。在本研究中，考虑了木质素在633 nm波长下的光吸收系数（ = 20476 m），以定义用于吸附分析的SPAR技术中使用的新虚折射率（）。在吸附模型中纳入该值后，得到的吸附量（）为1.11 mg/m²，品质因数（）为31.71 mg/m²。在较低浓度下，木质素在表面的沉积增加，在表面浓度为25 mg/L时产生的最大粘附系数 = 0.71。在35和45 mg/L的浓度范围内，木质素形成聚集体，其沉积量下降。石英晶体微天平（QCM）和SPAR技术的使用也证实，当使用较低浓度（5 - 25 mg/L）的木质素溶液进行吸附时，沉积的木质素吸附层中的水比例更大。本研究结果揭示了SPAR技术在评估木质素基材料在不同表面上的沉积性能方面的潜在用途，这将有助于木质素涂层和复合材料应用的开发。
