Location: Commodity Utilization ResearchTitle: Effects of rheology and viscosity of biobased adhesives on bonding performance
|BACIGALUPE, ALEJANDRO - National Institute Of Industrial Technology|
|ESCOBAR, MARIANO - National Institute Of Industrial Technology|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 11/16/2016
Publication Date: 2/14/2017
Citation: Bacigalupe, A., He, Z., Escobar, M.M. 2017. Effects of rheology and viscosity of biobased adhesives on bonding performance. In: He, Z., editor. Bio-based Wood Adhesives: Preparation, Characterization, and Testing. Boca Raton, Florida: CRC Press. pp. 293-309.
Interpretive Summary: Rheology is the science of deformation and flow of the matter due to the application of a force. From the practical point of view, the rheological properties are related to the ease of spread and flow over a surface. An adhesive with a high flow point value will not flow easily on the surface, resulting in undesirable bond strength, while adhesives with very low viscosity lead to excessive and undesirable water absorption and decreasing bonding properties. This chapter reviewed and discussed the rheological behavior and modification of some biobased (mainly protein) adhesive materials and their implication in adhesive or operative properties. As case studies and mostly per our published data, we presented more details on the effect of pH on rheology and viscosity of soy protein adhesives and the viscosity of cottonseed-base adhesive slurries. It is expected that the literature review of this chapter enrich the discussion and encourage the search for a relationship between the rheological properties and good bonding performance of protein-based adhesives.
Technical Abstract: Rheology is the science of deformation and flow of the matter due to the application of a force. Most rheological tests involve applying a force to a material and measuring its flow or change in shape. Rheological characterization is useful to study the flowability and viscoelastic properties of adhesive materials. This chapter reviews and discusses the rheological behavior of protein-based adhesives and their relationship with their bonding properties. Rheological characterization allows the analysis of the internal structure of the adhesives when they are modified by both physical and chemical processes. Most of the discussion focuses on soy-based adhesives and cotton modified by heat treatments, varying pH, enzymatic treatment and blending with commercial latex. Rheological characterization may also provide operational parameters for the preparation of wood composites. As an example, adhesives with a high flow point value will not flow easily on the surface of wood particles, hindering the dispersion of the adhesive and wetting of such particles.