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Action Clothes for Women Display
No full textThree guests view the Action Clothes for American Women display case and poster.https://digitalcommons.pittstate.edu/nellydonlecture/1079/thumbnail.jp
Marla Assists Model
No full textMarla Day helps a model put on a recreation of the Handy Dandy Apronhttps://digitalcommons.pittstate.edu/nellydonlecture/1080/thumbnail.jp
Apron Model
No full textModel showing off a recreation of the Handy Dandy Apronhttps://digitalcommons.pittstate.edu/nellydonlecture/1082/thumbnail.jp
BIO-BASED RIGID POLYURETHANE FOAMS USING MODIFIED HEMP SEED OIL COMBINED WITH FLAME RETARDANTS
Get PDFIn today\u27s world, the idea is to synthesize bio-based polyurethane (PU) goods, which reduces reliance on petroleum-based products. As a result, we produced polyol from hemp seed oil (HSO) and evaluated it using FTIR, GPC, hydroxyl value, and acid value. Hemp seed oil polyol (HSOP) was 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 (RPUFs) through the addition of flame retardants. The test results revealed that the HSO-based PU without flame retardants has 47.04 kg/m3 of apparent density, 92% closed cell content, and a compression strength of 252 kPa.
Regardless of the addition of flame retardants, the shape of the free-rise foams maintained their structure, suggesting that there is acceptable compatibility between the flame retardants and hemp oil-based polyurethane matrix.The physicochemical and mechanical properties, cell morphology, and thermal stability results further confirmed this observation. The majority of the RPUF presented a closed-cell content greater than 92%. 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 SOYBEAN OIL-BASED NON-ISOCYANATE POLYURETHANE FILMS VIA A SOLVENT AND CATALYST-FREE APPROACH
Get PDFSynthesizing polymeric materials that are both sustainable and practical has become a priority. Polyurethanes (PU) are becoming more popular because of their countless applications and exclusive properties in many sectors. While considering the current issue of environmental problems and the excessive use of petroleum products, non-isocyanate polyurethanes (NIPU) are favored due to their sustainability and low toxicity compared to conventional PU. In this work, flexible NIPU films were made using a green and facile method. For that, soybean oil (SBO) was used as the starting material and converted into epoxide soybean oil (ESBO) followed by its chemical conversion into carbonated soybean oil (CSBO) using carbon dioxide (CO2) gas. Following that, the CSBO reacted with three different aliphatic amines, namely 1,2-ethylenediamine (EDA), 1,4-butylenediamine (BDA), and 1,6-hexamethylenediamine (HDA) in a solventless and catalyst-free system. The films were cast and cured at 85 ℃ at different curing times. The effects of the aliphatic diamines and curing times on the NIPU films were evaluated. The individual materials were confirmed with FT-IR, 1H nuclear magnetic resonance, and gel permeation chromatography. To analyze the thermal and mechanical properties, thermogravimetric analysis, dynamic mechanical analysis, and differential scanning calorimetry were performed. Furthermore, mechanical tests such as hardness and tensile strength were also performed along with the degree of swelling, gel content, and contact angle using several solvents. This study elucidated the structure-property relationship based on the effect of curing time and aliphatic chain size of diamines in the properties of a NIPU film. The satisfactory thermal and mechanical properties accompanied by a green and facile approach displayed the potential scalability of the NIPU films
McCray in Winter
No full textMcCray during winter, the lawn and bushes are covered in snow.https://digitalcommons.pittstate.edu/mccraybuilding/1002/thumbnail.jp
Students Talking
No full textTwo students stand and talk in the Oval in front of McCrayhttps://digitalcommons.pittstate.edu/mccraybuilding/1044/thumbnail.jp
North Entrance of McCray
No full textBlack and white photo of McCray looking at the north entrance.https://digitalcommons.pittstate.edu/mccraybuilding/1045/thumbnail.jp
McCray Meeting Space
No full textClose up photo of the speaking area in front of the cross on the wall. The back is labeled Open College or Opera Collegehttps://digitalcommons.pittstate.edu/mccraybuilding/1049/thumbnail.jp
McCray Lobby
No full textBlack and white photo of McCray Lobby. The floor is tiled, a stringed instrument is depicted in the tile. The tiles go halfway up the wall and instrument tiles are on the border. A portrait of Walter R. McCray hangs above the firelplace. There is a metal railing lining the 2nd floor walkway above.https://digitalcommons.pittstate.edu/mccraybuilding/1051/thumbnail.jp