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Novel Binder System for Thermal Insulation, 2011 Innovative Nonwovens Conference

Novel Binder System for Thermal Insulation, 2011 Innovative Nonwovens Conference

Utilizing PLC outputs, 2011 Innovative Nonwovens Conference

Utilizing PLC outputs, 2011 Innovative Nonwovens Conference

Oil Absorbing Cotton Nonwoven Pads, 2011 Innovative Nonwovens Conference

Oil Absorbing Cotton Nonwoven Pads, 2011 Innovative Nonwovens Conference

Development of a 3D Scaffold Using Green Electrospinning, 2011 Innovative Nonwovens Conference

Development of a 3D Scaffold Using Green Electrospinning, 2011 Innovative Nonwovens Conference

Measurement and control of extensional viscosity in barrier coating dispersions, TAPPI Journal November 2023

ABSTRACT: This study aimed to understand the effect of various rheological additives on the extensional viscosity of barrier coating dispersions, as well as to understand the role extensional viscosity plays in stabilizing a liquid curtain. The apparent extensional viscosity was measured using two devices that create accelerating flows: a capillary viscometer and an orifice rheometer. Additives tested include several polyvinyl alcohols, a high molecular weight polyethylene oxide, and carboxymethylcellulose. Extensional viscosity plays a significant role in stabilizing a liquid curtain, as it slows down hole expansion and prevents impurities and disturbances from causing holes in the first place. Some of the additives could substantially increase the extensional viscosity of the dispersions without increasing the shear viscosity outside the typical range of processability for a curtain coater. Some of the additives exhibited coil-stretch transition, meaning they start increasing extensional viscosity above a certain extension rate. Polymers with low chain lengths exhibited finite extensibility, which indicates the polymer chain has fully extended and cannot provide further extensional viscosity, even though the extending force is increased. Polymeric additives with stiff or branched chains significantly raised shear viscosity without increasing extensional viscosity. Both methods could reliably measure extensional viscosity in curtain coating barrier dispersions.

SetPoint: That’s My Jam, November/December 2023 Paper360º

Numerical analysis of slot die coating of nanocellulosic materials, TAPPI Journal November 2020

ABSTRACT: Nanocellulosic coatings as a food packaging material are of commercial interest due to their nontoxic nature, renewability, and excellent barrier properties. Complex shear-thinning rheology poses challenges in designing and sizing equipment to pump, mix, and process the suspension and actual coating process. This study aims to determine the effectiveness of computational fluid dynamics (CFD) in predicting nanocellulosic suspension flow in light of existing rheological data. We employ and compare three distinct rheological models to characterize the rheology and flow of nanocellulose suspensions through a slot die coater, where the model parame-ters are established from existing slot rheometry measurements. A volume-of-fluid (VoF) based finite volume meth-od is employed to simulate the flow in a slot die operated in an unconventional metering mode. Results with the Casson model predict the presence of unyielded regions in the flow, which was not captured using the power law model. These stagnation regions will incur coatability issues stemming from flow intermittencies and lead to poten-tial defects in the coating layer, including fracture. The results suggest that a rheological model that includes yield stress should be considered while modeling such flows. A need for better rheological data to model nanocellulosic flows, especially at high consistencies and shear rates, is also highlighted.

The use of hollow sphere pigments as strength additives in paper and paperboard coatings—Part 2: Optimization in paperboard formulations for opacity and strength, TAPPI Journal November 2020

ABSTRACT: This report aims to summarize the efforts in testing the properties of coatings for paperboard utilizing hollow sphere pigments (HSPs). HSPs are known to effectively scatter light and replace titanium dioxide (TiO2) in architectural coating formulations. The effect of the particle size and void fraction was evaluated, along with many coating parameters, including level of addition, binder chemistry, and blends of two HSPs. The small HSPs that have optimized voids for scattering light showed equivalent strength to the TiO2-containing control. The strength data was surprising, particularly the improvement in strength for coatings containing large particle size HSPs. Because of this increase in strength, four parts of binder could be removed, which allowed for higher brightness while not compromising other properties, including hot melt glueability. These trends held true using different binder chemistries (styrene acrylic, vinyl acrylic, and styrene butadiene). Upon refining the formulations further, blends of two HSPs showed further benefit.

Rehabilitating Aging Plant Pipelines with Minimal Operational Downtime, 20PEERS Conference

Rehabilitating Aging Plant Pipelines with Minimal Operational Downtime, 20PEERS Conference

New Revenue Opportunities for Pulp and Paper Sector from Carbon Capture, 20PEERS Conference

New Revenue Opportunities for Pulp and Paper Sector from Carbon Capture, 20PEERS Conference