Thermal analysis and melt spinnability of poly(acrylonitrile-co-methyl acrylate) and poly(acrylonitrile-co-dimethyl itaconate) copolymers

2017 ◽  
Vol 88 (13) ◽  
pp. 1479-1490 ◽  
Author(s):  
Syang-Peng Rwei ◽  
Tun-Fun Way ◽  
Whe-Yi Chiang ◽  
Jen-Chun Tseng
Keyword(s):  
Thermal Analysis ◽  
Carbon Fiber ◽  
Low Temperature ◽  
Melting Temperature ◽  
Methyl Acrylate ◽  
Dwell Time ◽  
Molar Ratio ◽  
Poly Acrylonitrile ◽  
Feed Molar Ratio ◽  
Dimethyl Itaconate

This work investigated the cyclization possibility and melt spinnability of carbon fiber precursors, poly(acrylonitrile-co-methyl acrylate) (AN/MA) and poly(acrylonitrile-co-dimethyl itaconate) (AN/DMI). The onset temperature of cyclization of the AN/DMI copolymer is lower than that of the AN/MA copolymer and also the polyacrylonitrile (PAN) homopolymer. The enthalpy ( ΔH) of the AN/DMI copolymer is about 3–4 times that of the PAN homopolymer and about 1.8 times that of the AN/MA copolymer, indicating that the degree of cyclization of the AN/DMI copolymer is relatively higher. The melt dwell time of the AN/DMI copolymer is increased to about 3–5 times that of the AN/MA copolymer, especially when synthesized with a feed molar ratio of AN/DMI = 85/15. The AN/DMI copolymer (AN/DMI = 85/15) has the longest melt dwell time, 24.8 min, at the lowest melting temperature, 190oC, among all the PAN-related copolymers synthesized herein. Furthermore, the AN/DMI copolymer (AN/DMI = 85/15) can be rapidly cyclized at the cyclization temperature of 260℃, which is 25℃ lower than that of the AN/MA copolymer (AN/MA = 85/15). In short, this work demonstrates that the carbon fiber precursor made by the AN/DMI copolymer (AN/DMI = 85/15) will be superior to that of the AN/MA copolymer (AN/MA = 85/15) with respect to the melt spinnability and cyclization at low temperature.

scholarly journals Synthesis, spinning, and properties of very high molecular weight poly(acrylonitrile-co-methyl acrylate) for high performance precursors for carbon fiber

Polymer ◽  
2014 ◽  
Vol 55 (25) ◽  
pp. 6471-6482 ◽  
Author(s):  
E. Ashley Morris ◽  
Matthew C. Weisenberger ◽  
Stephanie B. Bradley ◽  
Mohamed G. Abdallah ◽  
Sue J. Mecham ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Carbon Fiber ◽  
High Molecular Weight ◽  
Methyl Acrylate ◽  
High Performance ◽  
Poly Acrylonitrile ◽  
Very High ◽  
High Molecular Weight Poly

Effects of Monomer Compatibility on Sizing Performance of Chitosan-g-P(MA-co-AM)

2021 ◽  
Vol 8 (6) ◽  
pp. 58-66
Author(s):  
Manli Li ◽  
Shuangshuang Wang ◽  
Enqi Jin ◽  
Bing Yu ◽  
Zhiyong Qiao
Keyword(s):  
Methyl Acrylate ◽  
Redox System ◽  
Molar Ratio ◽  
Application Performance ◽  
Overall Performance ◽  
Feed Molar Ratio

To impart good application performance to chitosan (CS) sizes for high polyester content warp yarns, methyl acrylate (MA) and acrylamide (AM) monomers, with a variation in feed molar ratio from 1:9 to 4:6, were grafted onto the molecular chains of native CS to obtain CS-g-P(MA-co-AM) products, with similar grafting ratios through a K2S2O8-NaHSO3 redox system. Effects of monomer compatibility of MA and AM on sizing performance of the CS-g-P(MA-co-AM) for high polyester content warp were studied. Grafting MA and AM with rational compatibility onto the molecular chains of CS is an effective method to improve the application performance of CS sizes. In view of the overall performance of the CS-g-P(MA-co-AM) sizes, the appropriate feed molar ratio of MA/AM should be 3:7.

Assembly of Hybrid Oligonucleotide Modified Gold (Au) and Alloy Nanoparticles Building Blocks

2006 ◽  
Vol 6 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Yu-Ching Kuo ◽  
Chun-Ping Jen ◽  
Yu-Hung Chen ◽  
Chia-Hao Su ◽  
Shu-Hui Tsai ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Melting Temperature ◽  
Hybrid Materials ◽  
Building Blocks ◽  
Au Nanoparticle ◽  
Molar Ratio ◽  
Alloy Nanoparticles ◽  
Modified Model ◽  
Nanoparticle Composites

The alloy-based hybrid materials with macroscopic network arrays were developed by AuAg/Au and AuAgPd/Au nanoparticle composites through oligonucleotides hybridization. AuAg/Au and AuAgPd/Au exhibited distinct organization. The morphology of AuAg/Au conjugation assembled mainly as compact aggregates while AuAgPd/Au hybrid conjugated into the loosen network assemblies. The dehybridization temperatures were studied as a function of molar ratio of alloy/Au. It was found that higher alloy/gold molar ratio led to stronger hybridization for alloy/gold composite, accompanied with increased melting temperature. These results could be interpreted in terms of more alloy nanoparticles bound to a Au particle when the molar ratio of alloy/gold increased. The thermal analysis also showed that AuAg/Au exhibited higher dehybridization temperature. A modified model describing the dehybridization probability of an intact Au/alloy aggregate was performed to support the dehybridization temperature increased with increasing alloy/Au molar ratio. As to more oligonucleotides carried by AuAg (4.9 ± 1.9 nm) than by AuAgPd (4.4 ± 1.5 nm) due to larger size in AuAg, the efficient hybridization could result in higher dehybridization temperature in AuAg/Au.

CERROLOW-117 Alloy

Alloy Digest ◽  
1978 ◽  
Vol 27 (10) ◽  
Keyword(s):  
Low Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Melting Temperature ◽  
Eutectic Alloy ◽  
Heat Treating ◽  
Dental Models ◽  
Metal Products

Abstract CERROLOW-117 Alloy is a bismuth-base eutectic alloy that melts at 117 F (47 C). Its low melting temperature and controlled-shrinkage characteristics make it very useful in industry for such applications as proof casting in tool and die shops, dental models and low-temperature solder. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on casting, forming, heat treating, and machining. Filing Code: Bi-8. Producer or source: Cerro Metal Products.

scholarly journals Fabrication and Characterization of Electrospun Poly(acrylonitrile-co-Methyl Acrylate)/Lignin Nanofibers: Effects of Lignin Type and Total Polymer Concentration

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 992
Author(s):  
Suchitha Devadas ◽  
Saja M. Nabat Al-Ajrash ◽  
Donald A. Klosterman ◽  
Kenya M. Crosson ◽  
Garry S. Crosson ◽  
...  
Keyword(s):  
Methyl Acrylate ◽  
Lignin Content ◽  
Polymer Concentration ◽  
Weight Ratio ◽  
Electrospun Nanofibers ◽  
Polymer Content ◽  
Blend Ratio ◽  
Blend Ratios ◽  
Poly Acrylonitrile

Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and dispersibility compared to LSL blends. Despite the lignin content or type, rheological studies demonstrated that PAN-MA concentration in solution dictated the blend’s viscosity. Smooth electrospun nanofibers were fabricated using AL depending upon the total polymer content and blend ratio. AL’s addition to PAN-MA did not affect the glass transition or degradation temperatures of the nanofibers compared to neat PAN-MA. We confirmed the presence of each lignin type within PAN-MA nanofibers through infrared spectroscopy. PAN-MA/AL nanofibers possessed similar morphological and thermal properties as PAN-MA; thus, these lignin-based nanofibers can replace PAN in future applications, including production of carbon fibers and supercapacitors.

Low-temperature fabrication of crystalline MnCoO spinel film on porous carbon paper for efficient oxygen evolution reaction

2021 ◽  
Author(s):  
Sunglun Kwon ◽  
Ha Eun Lee ◽  
Donghoon Han ◽  
Jong Hyeon Lee
Keyword(s):  
Thin Film ◽  
Carbon Fiber ◽  
Low Temperature ◽  
Oxygen Evolution ◽  
Porous Carbon ◽  
Oxygen Evolution Reaction ◽  
Carbon Paper ◽  
Carbon Fiber Paper

A thin film of MnxCo3−xO4 (MnCoO) nanocatalyst on a porous carbon fiber paper (CFP) electrode for efficient oxygen evolution reaction (OER).

scholarly journals Combined thermal analysis of plant oils

2021 ◽  
Author(s):  
Kinga Tamási ◽  
Kálmán Marossy
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Low Temperature ◽  
Glassy State ◽  
Mechanical Analysis ◽  
Plant Oils ◽  
Scanning Calorimetry ◽  
Natural Plant ◽  
The Moment ◽  
Current Reversal

AbstractThe paper deals with the study of seven selected natural plant oils. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and thermally stimulated discharge (TSD) methods were used. It has been found that most of the oils tested are in a glassy state at low temperature and have multiple transitions in the low temperature range. DSC shows complex melting-like processes or glass transition. For both DMA and TSD, the scaffold supportive method was used and found as a suitable one. DMA and TSD proved more sensitive than DSC and revealed at least two transitions between − 120 and − 40 °C. In the case of three oils (argan, avocado and sunflower), current reversal was observed by TSD; this symptom cannot be fully explained at the moment.

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