Microfliuidics to measure wetting properties of untreated/chemically treated steel and wood strands substrates

用于测量未经处理/化学处理的钢和木线基材的润湿特性的微流体

• 批准号: 515335-2017
• 负责人: Nazemifard, Neda
• 金额: $ 1.82万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=640601
• 关键词: Microfliuidics; measure; wetting; properties; untreated

Traditionally, formaldehyde based resins were used for manufacturing of engineered wood products (EWP)however the industry is shifting to the use of polymeric diphenylmethane diisocyanate (pMDI) binding resins.This shift is due to both the safety concerns with the use of formaldehyde, but also due to the significantadvantages with the use of pMDI including: reduced concentration and cost; fast curing; increased panelperformance through the formation of strong chemical bonds; increased strength and water resistance.However, there is a drawback limiting the use of pMDI due to its superior adhesive properties which requiresthe application of effective release agents (RA). RA prevents the sticking of the produced boards to the pressplates/belts resulting in downtime, costly cleaning and production losses. Guardian has previously developed aseries of Pressguard RA for pMDI bonded composite wood products which are protected by patents. Whilesuccessful, recent industry trends such as increased press temperatures as well as competitive market pressurerequires that we renew our research efforts in this field to regain lost market share and address the changingpress operating conditions. Development of efficient RA requires in depth understanding of their physicalproperties and wetting/adhesive interactions with the involved solid substrates, including stainless/mild steeland wood strands. The main objective of this joint project is to use microfluidic channels along with real-timehigh resolution microscopy to identify and measure the key physical properties that govern the adhesion/releasebetween hot metal plate and composite wood panels manufactured with pMDI resins. The experimental schemeincludes determination of dynamic surface tension, dynamic contact angles of pMDI resins, water, silicone oiland proprietary release agent (RA) blends. Microfluidic channels will be designed and fabricated in an attemptto act as micromodels to mimic the absorption of liquids in the wood porous structure. Different coating agentswill be used to change hydrophilicity/hydrophobicity of the channels to systematically study the effects ofsubstrate wettability on dynamic contact angle and capillary flow.

传统上，基于甲醛的树脂用于制造工程木制品（EWP），但是该行业正在转移到使用聚合物二苯基甲基甲烷二异氰酸酯（PMDI）结合树脂的转变。这是由于使用构成型hydife和PMDID的安全性而引起的。快速固化；通过形成牢固的化学键来提高经历性；强度和防水性的提高。但是，由于其出色的粘合性特性需要有效释放剂（RA），因此有缺点限制了PMDI的使用。 RA防止了粘贴在新闻板/皮带上的生产板，从而导致停机时间，昂贵的清洁和生产损失。 Guardian以前已经开发了PMDI键合的复合木制产品的PressGuard RA，并受到专利保护。虽然我们最近的行业趋势，例如升高的新闻温度以及竞争性的市场PressUrquires，我们在该领域重新恢复了该领域的研究工作，以恢复损失的市场份额并解决更换压力的运营条件。有效RA的开发需要深入了解其物理特性以及与所涉及的固体底物（包括不锈钢/低碳钢和木链）的润湿/粘合剂相互作用。该联合项目的主要目的是使用微流体通道以及实时高分辨率显微镜，以识别和测量使用PMDI树脂制造的热金属板和复合木板之间控制粘附/释放的关键物理特性。实验方案包括测定动态表面张力，PMDI树脂的动态接触角，水，硅油和专有释放剂（RA）混合物。微流体通道将在试图用作微型模型中设计和制造，以模仿木质多孔结构中液体的吸收。不同的涂层剂将用于改变通道的亲水性/疏水性，以系统地研究底层润湿性对动态接触角和毛细血管流动的影响。