@article{spence_venditti_rojas_habibi_pawlak_2011, title={A comparative study of energy consumption and physical properties of microfibrillated cellulose produced by different processing methods}, volume={18}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-011-9533-z}, DOI={10.1007/s10570-011-9533-z}, number={4}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Spence, Kelley L. and Venditti, Richard A. and Rojas, Orlando J. and Habibi, Youssef and Pawlak, Joel J.}, year={2011}, month={Apr}, pages={1097–1111} }
 @article{spence_venditti_rojas_pawlak_hubbe_2011, title={Water vapor barrier properties of coated and filled microfibrillated cellulose composite films}, volume={6}, DOI={10.15376/biores.6.4.4370-4388}, abstractNote={Microfibrillated celluloses (MFCs) have mechanical properties sufficient for packaging applications, but lack in comparison to petroleum-based plastics in water vapor barrier properties. These properties can be modified by the use of mineral fillers, added within the film structure, or waxes, as surface coatings. In this investigation it was found that addition of fillers resulted in films with lower densities but also lower water vapor transmission rates. This was hypothesized to be due to decreased water vapor solubility in the films. Associated transport phenomena were described by the Knudsen model for diffusion but due to the limited incorporation of chemical factors in the model, accurate prediction of pore diameters for filled films was not possible. Modeling the filled-films with Fick’s equation, however, takes into account chemical differences, as observed by the calculated tortuosity values. Remarkably, coating with beeswax, paraffin, and cooked starch resulted in films with water vapor transmission rates lower than those for low density polyethylene. These coatings were modeled with a three-layer model which determined that coatings were more effective in reducing WVTR.}, number={4}, journal={BioResources}, author={Spence, K. L. and Venditti, R. A. and Rojas, O. J. and Pawlak, J. J. and Hubbe, M. A.}, year={2011}, pages={4370–4388} }
 @article{spence_venditti_habibi_rojas_pawlak_2010, title={The effect of chemical composition on microfibrillar cellulose films from wood pulps: Mechanical processing and physical properties}, volume={101}, ISSN={0960-8524}, url={http://dx.doi.org/10.1016/j.biortech.2010.02.104}, DOI={10.1016/j.biortech.2010.02.104}, abstractNote={Films of microfibrillated celluloses (MFCs) from pulps of different yields, containing varying amounts of extractives, lignin, and hemicelluloses, were produced by combining refining and high-pressure homogenization techniques. MFC films were produced using a casting-evaporation technique and the physical and mechanical properties (including density, roughness, fold endurance and tensile properties) were determined. Homogenization of bleached and unbleached Kraft pulps gave rise to highly individualized MFCs, but not for thermo-mechanical pulp (TMP). The resulting MFC films had a roughness equivalent to the surface upon which the films were cast. Interestingly, after homogenization, the presence of lignin significantly increased film toughness, tensile index, and elastic modulus. The hornification of fibers through a drying and rewetting cycle prior to refining and homogenization did not produce any significant effect compared to films from never-dried fibers, indicating that MFC films can potentially be made from low-cost recycled cellulosic materials.}, number={15}, journal={Bioresource Technology}, publisher={Elsevier BV}, author={Spence, Kelley L. and Venditti, Richard A. and Habibi, Youssef and Rojas, Orlando J. and Pawlak, Joel J.}, year={2010}, month={Aug}, pages={5961–5968} }
 @article{spence_venditti_rojas_habibi_pawlak_2010, title={The effect of chemical composition on microfibrillar cellulose films from wood pulps: water interactions and physical properties for packaging applications}, volume={17}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-010-9424-8}, DOI={10.1007/s10570-010-9424-8}, number={4}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Spence, Kelley L. and Venditti, Richard A. and Rojas, Orlando J. and Habibi, Youssef and Pawlak, Joel J.}, year={2010}, month={May}, pages={835–848} }
 @article{spence_tucker_hart_2009, title={Comparison of various hardwood kraft pulp pre-bleaching techniques}, volume={8}, number={4}, journal={TAPPI Journal}, author={Spence, K. and Tucker, J. and Hart, P. W.}, year={2009}, pages={10–14} }
 @article{spence_venditti_rojas_2009, title={Sugar surfactants in paper recycling}, volume={24}, DOI={10.3183/npprj-2009-24-01-p107-111}, abstractNote={The objective of this research was to evaluate surfactants based on renewable materials (sugars and proteins) for use in ink removal from recycled paper via flotation deinking. By applying green chemistry approaches we aim to minimize the environmental impact of deinking agents and to open an avenue for a number of products that are being produced from natural resources. Foamability by the respective surfactants was considered and detergency experiments via piezoelectric sensing were used to reveal fundamental differences in terms of surfactant activity. Lab scale flotation deinking efficiency was measured primarily by image analysis and flotation yield determined gravimetrically. Based on deinking efficiency versus yield results, it was demonstrated that sugar-based surfactants are viable replacements to petroleum-based surfactants in flotation.}, number={1}, journal={Nordic Pulp & Paper Research Journal}, author={Spence, K. and Venditti, R. and Rojas, O. J.}, year={2009}, pages={107–111} }