This paper will discuss a novel blend of an ultraviolet light absorber and hindered amine light stabilizer that can be utilized in automotive and industrial coatings to provide excellent weathering performance. Our customers needed a light stabilizer blend with excellent weathering and low viscosity for ease of use, while also improving color and storage stability of the formulation prior to use. The synergistic combination of the UVA and non-interacting HALS protects against coating surface defects while also bolstering color and gloss retention in coating applications. The UV absorbance of the UVA-based blend provides suitability in a wide range of coatings on various substrates. The blend provides low color generation when exposed to high baking temperatures and/or extreme environmental conditions. The non-interacting HALS is especially suitable for oxidative curing and acid-catalyzed systems. The non-basic character of the HALS prevents potential interactions with acidic paint ingredients such as catalysts, biocides, and pigments.

Providing technology solutions that enable coatings to display dirt pickup resistance (DPR) has been a central theme in the development of exterior architectural paints. Dirt pick-up is a collective phenomenon comprising a multitude of mechanisms and interactions with a higher or a lower prevalence at different stages of exposure. The most reliable approach to characterize the resistance to soiling is the outdoor exposure of specimens under different climates and environments, followed by the surface evaluation using multiple standard tests. The goal of this work was to have a realistic estimation of DPR by allowing the paint films to weather under outdoor conditions. The films were examined using a set of measurements such as change in brightness (ΔL*), color (ΔE), dirt retention, and chalking. Atomic force microscopy and other surface specific methods were used to probe differences in paint film surface properties to rationalize observed variations in outdoor DPR performance.

Cobalt and certain Cobalt compounds have been determined to be possibly carcinogenic to humans, and therefore are becoming reclassified under CMR Cat.1B. Due to these legislations, allnex is launching new fully Cobalt-free driers for solvent-borne, high-solids, ultra-high-solids, 100% and water-based oxidative drying paint & ink systems. These ‘next-generation’ driers are highly efficient for set & through drying of alkyd paints used both in decorative and industrial applications, natural oils as well as air-drying inks. Deployed in modern alkyd resin based formulations, they fully comply with regulations, are free of hazardous labeling and low to near zero in VOC.

Recent studies into the root cause for paint failures in Architectural and Industrial Coatings indicate that pigment dispersants have a large impact on the performance and lifetime of a coating.  This study was done to investigate the relationship between dispersant type and coating performance.  Properties shown to be affected by the dispersant choice include stain resistance, wet scrub resistance, water resistance, and hardness after tinting.  The data measured shows that the choice of dispersant is critical.  By using the optimum dispersant type, compatibility is improved and the effect on coating lifetime will be discussed.

Polyurethanes have been widely used in the coatings industry due to their attractive properties of excellent durability and toughness, high chemical resistance and good hydrolytic stability; however, nowadays polyurethane coating formulations face a lot of challenges to meet the increasing demands for low V.O.C., environmentally-friendly and sustainable coatings. Cardolite developed a series bio-based, solvent-free and low viscosity polyols for various applications that could help formulators meet high-performance requirements and comply with health, safety and environmental regulations.
This paper will present the latest studies of new polyols in typical low V.O.C (<250g/L) protective coatings. The results demonstrated that those bio-based polyols could provide excellent performance, like fast cure, good mechanical properties, excellent abrasion resistance, good chemical resistance and low moisture sensitivity, and excellent adhesions to metal substrates. Furthermore, long-term salt spray exposure and cathodic disbondment test results revealed that those bio-based polyols could contribute excellent anti-corrosion performances to protective coatings.

Market demands are driving progressions in powder coatings technology to achieve greater durability at lower gloss ranges. Technology advancements in synthetic silica have led to the development of novel spherical particle designs with low porosity and surface area. These particles have a strong efficacy to matte powder coatings but also drive durability typically not achieved at lower gloss levels. This new silica technology gives the formulator a greater latitude to balance low gloss along with flexibility and hardness to better meet the requirements of the end application.
In this study, the paper reviews a range of additive technologies to matte powder coatings and highlights the new silica’s ability to balance low gloss, while improving hardness and flexibility. Key coating attributes, such as surface topography [with Hommel Tester 8000 instrument], resistance to film failure through deformation, as well as scratch and mar resistance will be highlighted in this performance benchmarking.

Epoxy resins are beneficial thermosetting polymers that function in wide range applications from adhesives to composites to protective coatings because of their outstanding properties. However, researchers have not been able to successfully replace the toxic BPA employed in the production of epoxy resins while retaining properties of the resins.

The United States generates over 80 million gallons of leftover architectural latex paint annually. This hazardous waste could end up in landfills if not appropriately treated or handled and can eventually contaminate our groundwater sources. Thanks to the American Coatings Association’s PaintCare program, more than 50 million gallons of this leftover paint is recycled.  By seeking inputs from recyclers, both from PaintCare participating and non-participating states, this research aims at investigating the role of the PaintCare program, its effectiveness, and the barriers for extending this program all across the United States. This research also dives into investigating the challenges in the recycling of paints other than latex-based architectural paints and identifying potential solutions. It appears that by creating awareness of the benefits of paint recycling among the end-users, the policy makes, and by legislative actions and collaborative action plans by all the stakeholders, a sustainable solution can be achieved.

 

The United States generates over 80 million gallons of leftover architectural latex paint annually. This hazardous waste could end up in landfills if not appropriately treated or handled and can eventually contaminate our groundwater sources. Thanks to the American Coatings Association’s PaintCare program, more than 50 million gallons of this leftover paint is recycled.  By seeking inputs from recyclers, both from PaintCare participating and non-participating states, this research aims at investigating the role of the PaintCare program, its effectiveness, and the barriers for extending this program all across the United States. This research also dives into investigating the challenges in the recycling of paints other than latex-based architectural paints and identifying potential solutions. It appears that by creating awareness of the benefits of paint recycling among the end-users, the policy makes, and by legislative actions and collaborative action plans by all the stakeholders, a sustainable solution can be achieved.

Additive Manufacturing (3D printing) technology is rapidly growing but there are various technical challenges. The parts printed by layer by layer assembly have inherently lower mechanical strength due to weak interfaces between the layers. This research has focused on developing a novel resin system with dual cure chemistry. The cure mechanisms are- rapid curing UV-initiated superbase catalyzed Michael Addition (MA)chemistry and a slower moisture-initiated condensation curing of organosilanes. Its hypothesized that a properly formulated thin resin layer upon exposure to UV source would rapidly achieve sufficient “green strength” by MA curing in the XY-plane allowing application of subsequent layers. The UV exposure would also hydrolyze, using ambient moisture, generating silanol groups. The silanol groups thus formed would slowly crosslink with X-Y and Z direction (between the layers). Thus, using two unique chemistries interlayer cross linking accomplished that would significantly reduce interfacial energies and improve mechanical properties of the printed part.

Grooming is the frequent and gentle cleaning of coatings to prevent the accumulation of marine fouling organisms. Grooming has been proposed as an effective technique to control fouling but could cause damage to non-durable coatings. This study set out to assess the grooming performance and the impact this grooming had on the surface of three biocide-free, durable siloxane polyurethane coatings and commercial coating. Coatings were statically immersed at Port Canaveral, Florida, and groomed every two weeks for five months with three different grooming treatments. Results showed that the ungroomed panels were heavily fouled with biofilm, tubeworms, barnacles, and bryozoan. The medium and heavy grooming brushes were able to control fouling coverage <5%, while the light grooming was only able to control coverage <50%. Surface characterization methods were used to analyze the coatings before and after grooming. It was concluded that the panels’ surface properties were unaffected by the grooming procedures.

In this study, a UV dual-cure system will be formulated with high bio-renewable content. Most commercial products are derived from non-renewable petrochemicals. Due to environmental concerns and regulations, the need for bio-renewable materials for coatings is increasing. This poster will present our work on a soybean oil-based UV dual-cure system. This study will investigate the effect of the secondary cure on film properties with varying curing mechanisms, degree of secondary cure, and sequence of curing mechanisms. The secondary curing mechanisms being explored are moisture cure and condensation cure. If successful, this coating has the potential of seeing application in UV-curing and 3D printing systems.

Non-isocyanate polyurethanes (NIPU) attract more attention these days due to the increasing environmental concerns from the traditional polyurethanes that involve isocyanates in the synthesis. Herein we prepared a novel one-package (1K) waterborne non-isocyanate polyurethane in this study. A series of 1K waterborne epoxy hybrid coatings were synthesized from bio-based amine, cyclic carbonate, internal emulsifier, and epoxy resin. The chemical structure of the NIPU polymers was analyzed by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The thermal stability and mechanical property of the 1K waterborne NIPU coatings were investigated by thermogravimetric analysis and tensile tests, respectively. The coatings with different formulations can achieve a broad range of thermal and mechanical properties. In addition, the general coating properties, such as hardness, adhesion, and chemical resistance, were evaluated to demonstrate the practical application of the 1K waterborne NIPU in coatings.

Colloidal unimolecular polymer (CUPs) are true nano scale size (3-9 nm) particles that are relatively easy to produce at low cost with zero VOCs and good structural variability which makes them a good candidate for coating applications. They can be used as coating resin, as co-resin, as reactive resin, as an additive or a catalyst.  CUP particles have a layer of surface water around them which can provide freeze thaw stability and wet edge retention to latex through a partial resin substitution, ~15%.  Producing CUPs on a large scale can be a challenge due to the slow rate of water addition required during the water reduction process to prevent non unimolecular collapse. To overcome this problem, a new delivery system which allows for faster water addition was successfully designed and tested on large size batch. The particle size results show successful CUP formation and further potential to scale-up capacity.

This study was focused on the preparation of coatings based on multifunctional bio-based resin —acrylated-epoxidized cottonseed oil (AECO). The synthesis process of the resin was performed by the epoxidation of cottonseed oil via the peracetic acid method, followed by the acrylation of the epoxidized oil using acrylic acid. This resin then was transformed into a crosslinked network by UV-radiation. In order to achieve high crosslink density and obtain coatings with good mechanical properties, formulations containing AECO were prepared with the addition of two different reactive diluents, such as: 1,6-hexandioldiacrylate and trimethylolpropane trimethacrylate. Coatings were photopolymerized using different weight ratios of reactive diluents and 2-hydroxy-2-methyl-1-phenylpropanone photoinitiator. Coating properties, such as hardness, adhesion, impact and chemical resistance were tested and thermomechanical properties were evaluated. The AECO based coatings were compared to the coatings based on already existing commercially available product —acrylated-epoxidized soybean oil (AESO).

Isabel Lambert, Madeleine Schleinitz, Isabel Gamez, and Shanju Zhang*
Department of Chemistry and Biochemistry, California Polytechnic State University, San Luis Obispo, CA 93407
Most paper packaging is coated in a petroleum based polymer to protect from moisture, oxidization, bacteria, etc. Unfortunately, such petroleum based polymer coating cannot be easily degraded or recycled, resulting in significant plastic pollution to the environment. Biodegradable alternatives such as poly(vinyl alcohol) (PVA) are highly desirable in the packaging industry although PVA does not have comparable properties to the petroleum based polymers. An effective method of producing high performance sustainable coatings is adding nanoparticles to the PVA coating. In this work, we report nanohybrid reinforced PVA coating of packaging paper. Nanohybrids consist of  1D cellulose nanofibrils (CNF) and 2D graphene oxide (GO). The coating formulation is prepared and the physical properties are investigated by means of various techniques.

Defect-free particulate coatings are an essential component of many consumer and industrial products. Most particulate coatings are deposited from dispersions or suspensions. Therefore, drying is a key stage in the coating process for determining coating microstructure, properties, and defects. Defects, such as cracks, curling, and delamination, originate from stress build-up within the coating layer during drying. Based on prior studies of stress and microstructure development, stress in particulate coatings is related to capillary pressure from curved menisci that form between particles within a drying particle network. Because water-borne hard particulate suspensions are especially prone to cracking whilst drying, the present work investigates coatings prepared from these suspensions with the aim of studying both crack-free and cracked coatings. Evidence of stress release upon fracture is observed with simultaneous imaging during cantilever beam deflection experiments. This poster will present these results and strategies to both systematically study stress-induced cracking and prevent it.