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Bio-Based Flame-Retardant and Smoke-Suppressing Wood Plastic Composites Enabled by Phytic Acid Tyramine Salt
Get PDFBio-based chemicals and waste plastic recycling play important parts in the development of a circular economy. Wood-plastic composites (WPCs), composed of recycled plastic and wood-processing residues, offer environmentally friendly alternatives. However, their inherent flammability poses fire hazards. While bio-based flame retardants offer advantages over conventional counterparts, their integration into WPCs remains underexplored. In response, a fully bio-based flame retardant, phytic acid-tyramine salt (PATA), was designed and synthesized using a green approach with deionized water as the solvent. PATA was then combined with ammonium polyphosphate (APP) to synergistically enhance the flame-retardant properties of WPCs. The PATA/APP system demonstrated significant improvements, augmenting flame retardancy and suppressing smoke generation. This system notably increased the limiting oxygen index by 31% and achieved a V-0 rating in vertical combustion tests. Moreover, it reduced the peak heat release rate, total heat release, and maximum smoke density by 49%, 22%, and 15%, respectively. During combustion, the PATA/APP system generated phosphoric acid substances, facilitating the formation of stable char layers containing P-N-C or P-O-C structures from wood flour decomposition. Overall, this study presents an environmentally friendly approach to enhance the flame retardancy of WPCs. By harnessing bio-based materials and recycling principles, the PATA/APP system offers a promising solution to mitigate fire risks associated with WPCs while contributing to the sustainable utilization of resources in the circular economy paradigm
Biobased High-Molecular-Weight Polyester with Impressive Elasticity, Thermo-Mechanical Properties, and Enzymatic Biodegradability: Replacing Petro-based PBAT
Get PDFThe widespread utilization of petroleum-based plastics causes environmental issues, prompting the production of biobased high-performance polymers for a sustainable future. With the application of multiple biobased monomers with comparable chemical structures in recent years, efforts are to made to explore or synthesize alternative polymers that has the advantages of plastic. In this study, we have synthesized poly (alkylene furanoate-co-sebacate) by two-stage melt polycondensation, utilizing biomass-derived substituent dimethyl furan 2,5-carboxylate and dimethyl sebacate, and different diols such as butane diol and pentane diol. The synthesized high-molecular weight aliphatic-aromatic polyesters, poly (butylene furanoate-co-sebacate) (PBFS) and poly (pentylene furanoate-co-sebacate) (PPeFS), were characterized by gel-permeation chromatography, FT-IR and NMR spectroscopies. The glycol chain length played a key role in determining the molecular weight, and physical properties of the polymer. The biobased polyester was successfully processed to thin films by compression molding and characterized for thermal, mechanical and enzymatic degradation properties. From the point of mechanical performance and enzymatic degradation, PBFS and PPeFS exhibited impressive elasticity upon stretching, which can be comparable to commercial PBAT. Moreover, chain extension reaction was also performed using intermediate polyol, where 0.5% 4,4′-methylene diphenyl diisocyanate was used as a coupling agent, to fabricate polyurethane adhesives. Therefore, these aliphatic-aromatic polyesters are potentially biobased and can offer both mechanical and biodegradable alternatives to petroleum-based PBAT
Determinants of Crime
Get PDFThis study examines the determinants of crime in metropolitan areas. Cities all around the world deal with crime. Crime detrimentally impacts society by impeding economic growth, social instability, undermining safety, and many more negative effects. This paper aims to use existing international research, thereby facilitating a comprehensive understanding of the determinants of crime in metropolitan areas. This research investigates certain socio-economic factors that influence the crime rate in metropolitan areas such as income, population density, and unemployment. The goal of this research is to contribute to bridging the gap in our understanding of the determinants of crime. By identifying and understanding the underlying causes of crime can lead to effective strategies for reducing the overall crime rate
Eclipse Viewing
No full textCarlie Payne and Carter Allender at the football field for the eclipse viewing party.https://digitalcommons.pittstate.edu/eclipse/1003/thumbnail.jp
Eclipse
No full textA picture of the eclipse through the telescopes provided at the event. It was a very neat view.https://digitalcommons.pittstate.edu/eclipse/1001/thumbnail.jp
Comparison of County and City Law Enforcement Agencies Responsibilities and its Effects on its Community Relationships
Get PDFThis study\u27s purpose was to identify the differences between two law enforcement agencies: Crawford County and the Girard Police Department. To do this I performed two ride-along and conducted interviews during those rides. After conducting my interviews and research, I then focused on analysis, and looking at how these differences affect the deputies and officers employed by the agency. I have also included research conducted from the last year. A small survey from students at Pittsburg State University and were asked how they felt towards their hometown law enforcement agencies. The purpose of this study was to find differences and similarities between the law enforcement agencies, considering their sizing, funding, and population they serve. The sampling was small and does not represent all law enforcement agencies within Kansas, Southeast Kansas, Crawford County, or the City of Girard. However, this research can be used to compare the two agencies and can help guide those interested in pursuing a career in law enforcement
Eclipse Sticker
No full textThis image was used for a limited edition sticker that CAC passed out to students during the Partial Eclipse Viewing Party.https://digitalcommons.pittstate.edu/eclipse/1006/thumbnail.jp
Horace Mann Laboratory School
No full textHorace Mann Laboratory School is located across the street north of the Library and provides accomdations for 250 children in Kindergarten and Grades 1 to 6https://digitalcommons.pittstate.edu/unihistoryphotos/1160/thumbnail.jp
Students with Animal Cage
No full text4 boys with a cage, possibly for a rabbit. Appear to be replacing the newspaper at the bottom.https://digitalcommons.pittstate.edu/unihistoryphotos/1184/thumbnail.jp
Typewriting Lesson - Grade 3
No full textMrs. Daphne Cross instructing four students on typewriting. Back labeled: Grade 3, Mrs. Daphne Cross, Supervisor. Dr. Jane M. Carroll, Director. Horace Mann Laboratory Schoolhttps://digitalcommons.pittstate.edu/unihistoryphotos/1194/thumbnail.jp