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Beyond the Fire: Natural Resource Management Techniques at Prairie State Park.
Get PDFThe tallgrass prairie ecosystem once spanned more than 70 million hectares of what is now the Midwestern United States, including eastern Kansas and western Missouri. Yet, only 4% of the tallgrass prairie remains intact, making it one of the most threatened ecosystems in North America. Two of the most serious threats to the remaining tallgrass prairie are woody encroachment and invasive plant species. Through a new partnership with Prairie State Park, five Pittsburg State University students worked with resource professionals to learn, practice, and apply prairie management techniques. We gained experience in the use of a chainsaw, UTV, ATV, brush cutter, propane torch, and backpack leaf blower for the overall goal of removing invasive red cedar (Juniperus virginiana) from the park. We assisted with winter vegetation management, including woody plant control and a prescribed burn. Our efforts created habitat for wildlife and helped to restore portions of the park that had become degraded due to woody encroachment. This new program collaborates with state agencies and will continue to prepare PSU students for careers in natural resource management and prairie restoration
Castor Oil-Based, Environmentally Friendly Using Melamine-Based Flame Retardants for Polyurethane Foam
Get PDFRigid foams, which are mostly used in the construction, refrigeration, and automotive industries, are one of the most important groups of polyurethanes with substantial potential for insulation and energy efficiency. Regrettably, stiff polyurethane foams often catch fire and are entirely combustible. They rapidly spread the flame as well. Rigid foams are considered hazardous materials because of all these potentially life-threatening situations and environmental issues. In response, nitrogen-based compounds have emerged as efficient, affordable, and ecologically friendly flame-retardant substitutes for halogenated compounds. It has been established that melamine derivatives should be included in stiff polyurethane foams to create nitrogen-based flame retardants. Because it includes melamine and its derivatives, which are also effective at stopping the spread of fire, the rigid foam is more thermally stable. This study found that the renewable resource castor oil (CO) allayed worries about environmental pollution. To improve production efficiency, sustainability, and compressive strength, CO-based multifunctional polyols were used in the synthesis of PU foam, which is widely used as an impact-absorbing material for protective gear. Two types of polyols based on castor oil with varied percentages of hydroxyl were prepared, and the viscosity of the blends was assessed. The physical, mechanical, and thermal properties of melamine (MA), melamine cyanurate (MC), and melamine phosphate (MP) at different concentrations were investigated in bio-based rigid polyurethane foam. In the burning test, the control foam burned for 49 seconds, losing 53.28% of its weight. Weight loss and the time it took for self-extinguishment were decreased by using more flame retardant than ordinary foam. Additionally, compared to foams based on MC, foams based on MA and MP showed a better level of thermal stability. The addition of MP and MA resulted in shorter burning times—9.5 and 14.4 seconds, respectively—and smaller weight losses—9.68% and 7.76%, respectively. When melamine-based flame retardants were added, there was less smoke and a quicker burning rate. It is possible to manufacture a bio-based polyurethane foam that exhibits suitable flame-retardant properties based on melamine, as the study reported here indicates. Thus, it was possible to use nitrogen-based flame retardants and castor oil polyol, two environmentally friendly ingredients, to improve the rigid polyurethane foams\u27 mechanical, thermal, and physical stability
Waste and New Canola Oils for Flame-Retardant Polyurethane Foams: A Comparative Study
Get PDFWaste cooking oil (WCO), obtained from cooking or frying food, poses a serious environmental risk when disposed of inappropriately. Therefore, finding ways to repurpose WCO into valuable products is important to mitigate environmental impact and health risks. This work focuses on utilizing used canola oil (UCO) to produce rigid polyurethane foams (RPUFs) as a sustainable approach to waste management and resource utilization. An epoxidation and ring-opening of UCO was employed to produce UCO-polyol for synthesizing RPUFs. Qualitative experiments such as epoxy, iodine, Fourier transform infrared (FTIR), and hydroxyl studies were carried out to evaluate the quality of UCO and UCO-based polyol, which were compared with new canola oil (NCO)-based polyol. Flame retardancy was improved by incorporating two flame retardants: dimethyl methyl phosphonate (DMMP) and expandable graphite (EG). The burning time of DMMP-contained foam was reduced from 54.95 s to 8.3 seconds, with weight loss from 55.25% to 12.10%. EG-treated foam also showed improvements in flame retardancy, with burning time reduced to 16.5 seconds and weight loss to 5.86%. The closed-cell content, an important factor for foam insulation applications, was around 90% of all the foams. Overall, the research demonstrates the feasibility and benefits of repurposing waste cooking oil to produce polyurethane foams, highlighting its potential for addressing environmental concerns and creating value from waste materials
Hemp Seed Oil Polyol-based Flame-Retardant Rigid Polyurethane Foams
Get PDFIn today\u27s world, the idea is to synthesize bio-based polyurethane goods, which reduces reliance on petroleum-based products. As a result, we produced polyol from hemp seed oil (HSO) and evaluated it using FTIR, hydroxyl value, and acid value. Polyol is successfully synthesized and combined with additional ingredients such as catalysts, blowing agents, hardeners, and flame-retardant chemicals to produce stiff polyurethane foams. The focus of this research was to synthesize high-quality flame-retardant rigid polyurethane foams (RPUF) through the addition of flame retardants. Within this line, the majority of the RPUF presented a closed-cell content greater than 65%. Also, a considerable improvement in flame retardancy was observed as the neat HSO-based RPUF had a burning time of 110 seconds and a weight loss of 82%. Yet, the addition of 10 wt% of triethyl phosphate (TEP) reduced to 19 seconds and 5%, respectively. The addition of other two flame retardants, dimethyl methyl phosphate (DMMP) and expandable graphite (EG), also showed similar trends with flame retardancy and mechanical properties. As a result, our research on the manufacture of biobased RPUFs was successful
Study of Thermal and Mechanical Properties of Bio-based Foam using Phosphorous and Nitrogen-based Flame Retardants
Get PDFPolyurethanes (PUs) are defined as synthetic copolymers prepared using polyols and polyisocyanates. They have a wide range of applications in a variety of products, such as furniture, medical equipment, packaging, foams, coatings, elastomers, and adhesives. Out of all these, one of the most significant commercial products is polyurethane foams (PUFs). However, most of the raw materials used for PUFs production originate from non-renewable sources and due to their highly porous nature, these foams are highly flammable. It is considered essential to combine bio-based components to produce polyurethanes with good flame retardancy. Thus, introducing halogen-free flame retardant is a primary requirement to synthesize PUFs. In this research work, soybean oil (SO) was chemically modified into soybean oil polyol (SOP) through epoxidation and ring-opening reactions. The synthesized chemicals were characterized using FT-IR, GPC, viscosity, and hydroxyl value. Also, three different halogen-free flame retardants (FRs) were introduced to reduce the flammability of PUFs. Melamine (MA), ODOPM-CYC, and DOPO (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) were used as flame-retardants in this study. Different amounts of FRs were added to the RPUFs to evaluate their effect on PUFs properties. Physical, thermal, morphological, and mechanical properties were evaluated. Results showed a decreasing trend in burning time after the addition of an increasing amount of FRs in PUFs. The lowest flame duration of 5.1 seconds and weight loss of 1.28% were observed for foam containing ODOPM-CYC as FRs
Rubber Seed Oil-Based UV-Curable Polyurethane Acrylate Resins for Digital Light Processing (DLP) 3D Printing
Get PDFNovel UV-curable polyurethane acrylate (PUA) resins were developed from rubber seed oil (RSO). Firstly, hydroxylated rubber seed oil (HRSO) was prepared via an alcoholysis reaction of RSO with glycerol, and then HRSO was reacted with isophorone diisocyanate (IPDI) and hydroxyethyl acrylate (HEA) to produce the RSO-based PUA (RSO-PUA) oligomer. FT-IR and 1H NMR spectra collectively revealed that the obtained RSO-PUA was successfully synthesized, and the calculated C=C functionality of oligomer was 2.27 per fatty acid. Subsequently, a series of UV-curable resins were prepared and their ultimate properties, as well as UV-curing kinetics, were investigated. Notably, the UV-cured materials with 40% trimethylolpropane triacrylate (TMPTA) displayed a tensile strength of 11.7 MPa, an adhesion of 2 grade, a pencil hardness of 3H, a flexibility of 2 mm, and a glass transition temperature up to 109.4 ◦C. Finally, the optimal resin was used for digital light processing (DLP) 3D printing. The critical exposure energy of RSO-PUA (15.20 mJ/cm2) was lower than a commercial resin. In general, this work offered a simple method to prepare woody plant oil-based high-performance PUA resins that could be applied in the 3D printing industry
Spatiotemporal Changes in the Imperiled and Diverse Mussel Assemblage of the Spring River in Response to Known and Emerging Pollutants
Get PDFThe Spring River of southeastern Kansas is home to a diverse assemblage of 34 mussels, many of which are imperiled. Elevated metal concentrations that resulted from past mining for lead and zinc in the Tri-State Mining District historically imperiled Spring River mussels, but this threat has abated over the last 20 years. Ammonia pollution may have replaced the threat of metals however, with potentially severe consequences for Spring River mussels. Our objectives were to evaluate spatiotemporal trends in density and richness of Spring River mussels in relation to changing concentrations of metals and ammonia. We accomplished this objective by performing quantitative mussel surveys across eleven Spring River sites during the summer of 2023, and we then compared our data to surveys performed during 1993-1995 and 2003-2005. We found that mussel densities had declined in the upper Spring River reach that historically was minimally-impacted by metals, while densities in the previously metal-contaminated reach above Empire Lake had increased. Mussel density and richness below Empire Lake were low historically and remain as such. These patterns were consistent with ammonia as the causative agent behind mussel declines in the upper reach, as concentrations were highest near the Missouri border and decreased downstream
Architect Sketch
No full textStylized drawing of McPherson Nurse Education Buildinghttps://digitalcommons.pittstate.edu/mcphersonbuilding/1005/thumbnail.jp
Her Big Idea was Born
Get PDFAn exhibit display for the Nelly Don Gene DeGruson Lecture, text created by Sara DeCaro, design by Angelica Abshire, and editing by Rafael Almeida.https://digitalcommons.pittstate.edu/nellydonlecture/1005/thumbnail.jp
Angel and Janette at the Lecture
No full textAngel Abshire and Janette Mauk talk over cookies and drinkshttps://digitalcommons.pittstate.edu/nellydonlecture/1012/thumbnail.jp