环氧树脂涂层表面亲水性对微藻黏附性能的影响

在固体材料表面黏附成膜是微藻细胞的一种生理特性。近些年基于微藻生物膜的生物过程，如生物膜贴壁培养和防附着技术受到了很多关注。微藻在固体材料表面的黏附受藻细胞与材料表面之间的相互作用的影响，建立黏附强度与材料表面性质参数间的关系对于通过材料选择来强化或控制微藻生物膜具有非常重要的意义。本工作的目的是揭示和明确材料亲疏水性对微藻黏附的影响，提出了一种双酚A环氧(EP)树脂表面亲疏水改性的方法。通过将亲水性的二乙醇胺(DEA)或疏水性的聚甲基聚硅氧烷(PMHS)加入到EP树脂中反应，EP树脂表面水接触角在36.80?~98.34?范围内可通过加入不同量的DEA或PMHS实现任意可调，材料的表面水接触角与DEA或PMHS加入量之间有线性关系。重要的是这种改性方法获得的材料，其形貌、结构、表面粗糙度等表面性质几乎没有变化，从而在研究和关联微藻黏附量与材料表面亲疏水性(表面水接触角)之间的关系时可以排除亲疏水性之外的其他表面性质的影响；其次，考察了小球藻和栅藻在不同亲疏水性材料表面的黏附行为，结果表明小球藻和栅藻在亲水性和疏水性材料表面均能黏附成膜，但在亲水性材料表面黏附更多更快；建立了微藻最大黏附容量与材料表面接触角之间关联关系，表明微藻最大黏附容量随材料表面水接触角的增大而线性降低，栅藻的表面黏附容量比小球藻大。

Influence of surface hydrophobicity of epoxy resin coatings on microalgae adhesion property

Formation of bio?lm on solid surfaces is a common feature of microalgae, which is tightly associated with the properties of microalgae and substratum material. Increasing interests on microalgae biofilm attached cultivation or antifouling require to determine the effect of material surface physico-chemical characteristics on algal adhesion. However, reference researches are usually inconclusive and do not work well. This work is to evaluate the influence of hydrophobicity/hydrophilicity of substratum on microalgae adhesion. First, this work reported a novel method for surface hydrophobic modification of bisphenol-A Epoxy (EP) resin by adding hydrophilic diethanolamine (DEA) or hydrophobic polymethylhydrosiloxane (PMHS). The results showed that the water contact angles of the modified EP resin coatings were regulated in the range from 36.80? to 98.34?. With the increase of DEA, the water contact angle linearly declined. While, with the increase of PMHS, the water contact angle linearly increased. However, little difference between the two kinds of modified EP materials was observed through the characteristics of morphology, surface texture and roughness. Then, the static adhesion of microalgae C. vulgaris and S. dimorphus was investigated. The results showed that both C. vulgaris and S. dimorphus could adhere on all the coating surfaces with different wettabilities, but preferred to adhere more and faster on the hydrophilic ones. The linear relationships of two microalgae between their maximum adhering capacities and the water contact angles of the modified EP coatings were existed respectively. Hydrophobic surface had less adhered algal cells. The adhesion amount of S. dimorphus was larger than that of C. vulgaris.