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<p>In this study new value-added products were developed from four commercially available refined waxes for use as commercial emulsifiers via the technique of maleation. This research was performed in collaboration with an industrial partner with the hope of developing a wax emulsifier product that could replace commercially used wax emulsifiers in engineered wood product emulsions at a cost reduction by beginning with the design of a cost effective process that could be incorporated into an existing factory production line. Through the investigation and subsequent optimization of this process, a highly maleated product was achieved using 6 different quick and simple approaches. A standardized experimental design was applied to the parameters of the experiment: reaction time, peroxide, starting wax, maleic anhydride concentration, and temperature to observe and understand the individual effects of each on the resultant final product. Three organic peroxide initiators were evaluated; di-<em>tert</em>-butyl peroxide, di-<em>tert</em>-butyl peroxybenzoate and benzoyl peroxide, as well as a thermally initiated approach. The resultant waxes were then identified by their acid number and drop melt point; and from this, the overall efficiency of the combined parameter levels was calculated as a function the initial maleic anhydride amount versus that of the final. The maleated wax emulsifiers were incorporated into emulsions and applied to engineered wood products. Emulsifiers made via the thermally initiated approach showed statistically significant improvements in the desired properties, water absorbance and thickness swell, of the engineered wood products as compared to a commercial control formulation.</p> / Master of Science (MSc)

As energy prices and demand are projected to increase globally and markets become more competitive nationally and internationally; the wood products industry must find ways to remain relevant. By: 1) analyzing energy-saving recommendations contained in the IAC database; 2) comparing those recommendations by criteria such as cost, savings, and payback period; 3) identifying recommendations that incorporate lean manufacturing principles; and 4) investigating the practices and perceptions of manufacturers at the facility level, this project provides information for identifying the greatest opportunities for energy management among U.S. wood product manufacturers. Results from the analysis of the IAC database show that wood product manufacturers had a low implementation rate of energy recommendations ranked purely by cost, savings, and payback period among wood product manufacturers suggesting they were not focused on implementing energy recommendations specifically based on those criteria. While some recommendations were found to be statistically different in at least one criteria: cost, savings, or payback period between wood and non-wood manufactures as well as primary and secondary wood manufacturers, only two recommendations had practical differences, large payback periods, between primary and secondary wood manufacturers. Twenty-four of 192 energy recommendations were classified as lean-based energy recommendations using the Kirby and Green (2003) methodology, however, there was no clear evidence to suggest the lean-based energy recommendations were superior in terms of cost, savings, or payback period when compared to simple energy recommendations. Interviews with primary and secondary manufacturers revealed a lack of commitment to energy performance improvement and the reported barriers of implementation among a small sample of wood products manufacturers suggests that the dissemination of energy management knowledge and benefits is a problem. / Master of Science

Increasing awareness of sustainable building materials has led to interest in enhancing the structural performance of engineered wood products. Wood is a sustainable, renewable material, and the increasing use of wood in construction contributes to its sustainability. Multi-layer wooden panels are one type of engineered wood product used in construction. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. Assembly techniques considered in the earliest stages of this research work were laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. Cross-laminated timber (CLT) was found to offer some advantages over these other techniques. It is cost-effective, not patented, offers freedom of choice regarding the visibility of surfaces, provides the possibility of using different timber quality in the same panel at different points of its thickness, and is the most well-established assembly technique currently used in the industrial market. Building upon that foundational work, the operational capabilities of CLT were further evaluated by creating panels with different layer orientations. The mechanical properties of CLT panels constructed with layers angled in an alternative configuration produced on a modified industrial CLT production line were evaluated. Timber lamellae were adhesively bonded in a single-step press procedure to form CLT panels. Transverse layers were laid at a 45° angle instead of the conventional 90° angle with respect to the longitudinal layers’ 0° angle. Tests were carried out on 40 five-layered CLT panels, each with either a ±45° or a 90° configuration. Half of these panels were evaluated under bending: out-of-plane loading was applied in the principal orientation of the panels via four-point bending. The other twenty were evaluated under compression: an in-plane uniaxial compressive loading was applied in the principal orientation of the panels. Quasi-static loading conditions were used for both in- and out-of-plane testing to determine the extent to which the load-bearing capacity of such panels could be enhanced under the current load case. Modified CLT showed higher stiffness, strength, and fifth-percentile characteristics, values that indicate the load-bearing capacity of these panels as a construction material. Failure modes under in- and out-of-plane loading for each panel type were also assessed. Data from out-of-plane loading were further analysed. A non-contact full-field measurement and analysis technique based on digital image correlation (DIC) was utilised for analysis at global and local scales. DIC evaluation of 100 CLT layers showed that a considerable part of the stiffness of conventional CLT is reduced by the shear resistance of its transverse layers. The presence of heterogeneous features, such as knots, has the desirable effect of reducing the propagation of shear fraction along the layers. These results call into question the current grading criteria in the CLT standard. It is suggested that the lower timber grading limit be adjusted for increased value-yield. The overall experimental results suggest the use of CLT panels with a ±45°-layered configuration for construction. They also motivate the use of alternatively angled layered panels for more construction design freedom, especially in areas that demand shear resistance. In addition, the design possibility that such 45°-configured CLT can carry a given load while using less material than conventional CLT suggests the potential to use such panels in a wider range of structural applications. The results of test production revealed that 45°-configured CLT can be industrially produced without using more material than is required for construction of conventional 90°-configured panels. Based on these results, CLT should be further explored as a suitable product for use in more wooden-panel construction. / <p>External cooperation: Martinson Group AB and Research Institutes of Sweden (RISE)</p>