Structure and properties of a phenylethynyl-terminated PMDA-type asymmetric polyimide

2018 ◽  
Vol 31 (3) ◽  
pp. 261-272 ◽  
Author(s):  
Yixiang Zhang ◽  
Masahiko Miyauchi ◽  
Steven Nutt
Keyword(s):  
Mechanical Properties ◽  
Thermal Processing ◽  
Amorphous Structure ◽  
Decomposition Temperature ◽  
Thermal And Mechanical Properties ◽  
Chain Mobility ◽  
Amorphous Structures ◽  
The Cross ◽  
Imide Oligomers ◽  
The Relationship

A new polymerized monomeric reactant (PMR)-type polyimide, designated TriA X, was investigated to determine polymer structure, processability, thermal, and mechanical properties and establish the relationship between the molecular structure and those properties. TriA X is a PMR-type polyimide with an asymmetric, irregular, and nonplanar backbone. Both the imide oligomers and the cross-linked polyimides of TriA X exhibited loose-packed amorphous structures, independent of thermal processing. The peculiar structures were attributed to the asymmetric backbone, which effectively prevented the formation of closed-packed chain stacking typically observed in polyimides. The imide oligomers exhibited a lower melt viscosity than a control imide oligomer (symmetric and semi-crystalline), indicating a higher chain mobility above the glass transition temperature ( Tg). The cured polyimide exhibited a Tg = 362°C and a decomposition temperature = 550°C. The cross-linked TriA X exhibited exceptional toughness and ductility (e.g. 15.1% at 23°C) for a polyimide, which was attributed to the high-molecular-weight oligomer and loose-packed amorphous structure. The thermal and mechanical properties of TriA X surpass those of PMR-15 and AFR-PE-4.

The effect of bis allyl benzoxazine on the thermal, mechanical and dielectric properties of bismaleimide–cyanate blend polymers

RSC Advances ◽  
2015 ◽  
Vol 5 (72) ◽  
pp. 58821-58831 ◽  
Author(s):  
Yiqun Wang ◽  
Kaichang Kou ◽  
Guanglei Wu ◽  
Ailing Feng ◽  
Longhai Zhuo
Keyword(s):  
Mechanical Properties ◽  
Dielectric Properties ◽  
Polymer Composite ◽  
High Performance ◽  
Cross Linking ◽  
Thermal And Mechanical Properties ◽  
High Performance Polymer ◽  
The Cross

A high-performance polymer composite was fabricated using Bz-allyl/BMI/BADCy resin, in which the BMI/BADCy resin was modified with Bz-allyl to improve its dielectric, thermal and mechanical properties and the cross-linking degree after curing.

NiTi Shape Memory Alloy Wire’s Constitutive Describe at Different Temperatures

2017 ◽  
Vol 729 ◽  
pp. 13-17
Author(s):  
Guang Yong Yang ◽  
Yang Zhong ◽  
Zhi Fei Qiu ◽  
Jun Wang ◽  
Wei Na Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Niti Shape Memory Alloy ◽  
Thermal And Mechanical Properties ◽  
Restoring Force ◽  
Intelligent Material ◽  
Different Temperatures ◽  
Relationship Of ◽  
The Relationship

NiTi shape memory alloy is an intelligent drive and awareness materials which develop very rapidly and is used in many fields in recent years, whose mechanical properties are not only related to chemical composition, but also closely related to the temperature. This article aims to study the NiTi shape memory alloy wire’s constitutive behavior coupled thermal and mechanical properties at different temperatures. By analyzing the results, the relationship of NiTi shape memory alloy between deformation and the restoring force at elevated temperature is obtained, thus providing a basis for the engineering design and simulation process of NiTi intelligent material.

Study on Thermal and Mechanical Properties of Polyurethane Systems for In-Mould Decoration Ink

2014 ◽  
Vol 881-883 ◽  
pp. 850-853
Author(s):  
Jing Lin ◽  
Cheng Zheng ◽  
Shu Xuan Qian ◽  
Xian Fang Cai ◽  
Yong Shun Lan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Sorption ◽  
Phenolic Resin ◽  
Cross Linking ◽  
Thermal And Mechanical Properties ◽  
Elongation At Break ◽  
Swell Ratio ◽  
System A ◽  
Gel Fraction ◽  
The Cross

In this study, three polyurethane systems A (A450/RD181/L75), B(A450/RD181/N3390) and C(A450/RD181/2104/N3390) for in-mould decoration ink were studied. The results of thermogravimetric analysis showed that introducing rosin modified phenolic resin 2104 (RMPR) and N3390 into PU system A can improve the thermal stability, Moreover, Measurements of gel fraction and swell ratio showed that incorporation of N3390 is benificial for increasing the cross-linking density of PU systems as compared to L75 so as to increase the gel fraction and decrease the swell ratio.The tensile strength of cured PU systems increased following in the order: A<B<C, elongation at break is just the opposite. In addition, it is indicated that incorporation of N3390 is benificial for increasing the cross-linking density of PUs so as to improve the the shore A hardness and decease the water sorption.

scholarly journals Processing and Characterisation of Banana Leaf Fibre Reinforced Thermoplastic Cassava Starch Composites

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1420
Author(s):  
Ridhwan Jumaidin ◽  
Nuraliah Ahmad Diah ◽  
R. A. Ilyas ◽  
Roziela Hanim Alamjuri ◽  
Fahmi Asyadi Md Yusof
Keyword(s):  
Mechanical Properties ◽  
Decomposition Temperature ◽  
Cassava Starch ◽  
Thermal And Mechanical Properties ◽  
Good Adhesion ◽  
Intermolecular Hydrogen Bonds ◽  
Morphological Studies ◽  
Ft Ir ◽  
Banana Leaf ◽  
Thermal Stability Of

Increasing environmental concerns have led to greater attention to the development of biodegradable materials. The aim of this paper is to investigate the effect of banana leaf fibre (BLF) on the thermal and mechanical properties of thermoplastic cassava starch (TPCS). The biocomposites were prepared by incorporating 10 to 50 wt.% BLF into the TPCS matrix. The samples were characterised for their thermal and mechanical properties. The results showed that there were significant increments in the tensile and flexural properties of the materials, with the highest strength and modulus values obtained at 40 wt.% BLF content. Thermogravimetric analysis showed that the addition of BLF had increased the thermal stability of the material, indicated by higher-onset decomposition temperature and ash content. Morphological studies through scanning electron microscopy (SEM) exhibited a homogenous distribution of fibres and matrix with good adhesion, which is crucial in improving the mechanical properties of biocomposites. This was also attributed to the strong interaction of intermolecular hydrogen bonds between TPCS and fibre, proven by the FT-IR test that observed the presence of O–H bonding in the biocomposite.

Effect of highly thermally conductive Ag@BN on the thermal and mechanical properties of phthalonitrile resins

2021 ◽  
pp. 095400832110580
Author(s):  
Xinggang Chen ◽  
Xiongwei Qu ◽  
Jun Chen ◽  
De Zheng
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Thermal Stability ◽  
Storage Modulus ◽  
Dynamic Mechanical Properties ◽  
Decomposition Temperature ◽  
Potential Candidate ◽  
Thermal And Mechanical Properties ◽  
X Ray ◽  
Thermally Conductive

Ag@BN/phthalonitrile resin composites were prepared using highly thermally conductive BN modified by Ag plating. The effects of different contents of Ag@BN particles on the dynamic mechanical properties, thermal stability, and thermal conductivity of composites were examined. The results of Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analyses showed that Ag was successfully deposited on the surface of BN. The prepared Ag@BN was subjected to KH550 grafting treatment. With the increase in the content of Ag@BN/KH550, the storage modulus, thermal stability, and thermal conductivity of the composite increased. The storage modulus, decomposition temperature, and thermal conductivity of the Ag@BN/phthalonitrile composite with 20 wt.% Ag@BN/KH550 were 5.0 GPa, 539°C, and 0.80 W/(mK), respectively, which are 1.35, 1.18, and 3.33 times higher than those of pure resin, respectively. The compatibility and dispersibility of BN modified by Ag plating in phthalonitrile resin were effectively enhanced, thereby providing a potential candidate to be used at high-temperature devices with high thermal conductivity.

scholarly journals Preparation of Polypropylene/Bentonite Composites of Enhanced Thermal and Mechanical Properties using L-leucine and Stearic Acid as Coupling Agents

2021 ◽  
Vol 11 (3) ◽  
pp. 7207-7216
Author(s):  
N. Mohammedi ◽  
F. Zoukrami ◽  
N. Haddaoui
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Stearic Acid ◽  
Decomposition Temperature ◽  
The Other ◽  
Morphological Observation ◽  
Coupling Agents ◽  
Thermal And Mechanical Properties ◽  
Melt Mixing ◽  
Elongation At Break

The compatibilization of raw bentonite (bent) with a polymer matrix of polypropylene (PP) can improve the performance of the material in terms of thermal and mechanical properties. In this study, two kinds of untreated bentonite, bentonite-Maghnia (bent-m) and bentonite-Mostaganem (bent-M), that differ in the proportion of Al2O3 and in the particle size distribution were coupled to typical maleic anhydride grafted polypropylene PP-MA. Stearic Acid (SA) and L-leucine Amino Acid (AA) were selected as new coupling modifiers at a 5/5 ratio of bentonite/coupling agent. All PP/bent composites were prepared by melt mixing at 190°C. Morphological observation revealed a good dispersion of bentonite into the PP matrix in the presence of AA, SA, and PP-MA. Mechanical properties showed an increase in stiffness as bent-m or bent-M were associated with AA. For instance, PP/bent-m/AA composite underwent an improvement of about 13% in Young’s modulus as compared to neat PP. On the other hand, the addition of SA into bent-m maintained stiffness and tensile strength at an acceptable level. An increase of around 40°C and 37% in the decomposition temperature and elongation at break was respectively observed for the PP/bent-m/SA composite. All coupled composites showed high degradation temperatures.

Thermal and Mechanical Properties of Natural Rubber/Rice Starch Interpenetrating Network Hydrogel

2013 ◽  
Vol 844 ◽  
pp. 77-80
Author(s):  
Warisada Sila-On ◽  
Jatuporn Pratoomted ◽  
Utsana Puapermpoonsiri ◽  
Chaiwute Vudjung ◽  
Wiwat Pichayakorn
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Mechanical Strength ◽  
Natural Rubber Latex ◽  
Amorphous Structure ◽  
Mechanical Tests ◽  
Rice Starch ◽  
Thermal And Mechanical Properties ◽  
Interpenetrating Networks ◽  
Scanning Calorimetry

Novel hydrogels based on natural rubber latex (NRL) and rice starch (RSt) (1:2 ratio) were prepared with various amount of N,N-methylenebisacrylamide (MBA) and 2.5 phr of maleic acid to form interpenetrating networks (IPN) using free-radical polymerization technique. The thermal and mechanical properties were performed by differential scanning calorimetry and mechanical tests. From data obtained, the change in Tg of rubber and melting point of RSt indicated that polymer-polymer interaction could be formed in IPN hydrogel. The higher amount addition of MBA created more mechanical strength of IPN hydrogels caused by the higher of interlacement formation. However, their mechanical strength of such hydrogels was lower than that of NRL alone due to the formation of amorphous structure in IPN hydrogel. These IPN hydrogels also improved the swelling property which will be utilized for wound healing application.

Chain Mobility, Thermal, and Mechanical Properties of Poly(ethylene furanoate) Compared to Poly(ethylene terephthalate)

2014 ◽  
Vol 47 (4) ◽  
pp. 1383-1391 ◽  
Author(s):  
Steven K. Burgess ◽  
Johannes E. Leisen ◽  
Brian E. Kraftschik ◽  
Christopher R. Mubarak ◽  
Robert M. Kriegel ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Ethylene Terephthalate ◽  
Thermal And Mechanical Properties ◽  
Chain Mobility ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Thermal and Mechanical Properties of Mulch Film from Poly(Lactic Acid)/Expoxidized Natural Rubber Blends Filled with Rutile TiO2 as Fillers

2013 ◽  
Vol 844 ◽  
pp. 65-68
Author(s):  
Pranee Nuinu ◽  
Kittikorn Samosorn ◽  
Kittisak Srilatong ◽  
Siripa Tongbut ◽  
Sayant Saengsuwan
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Thermal Stability ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Natural Rubber ◽  
Decomposition Temperature ◽  
Poly Lactic Acid ◽  
Thermal And Mechanical Properties ◽  
Thermal Stability Of

The aim of this research was to reduce and improve the brittleness and thermal properties of poly lactic acid (PLA), respectively. Epoxidized natural rubber (ENR) was used to enhance the toughness and rutile titanium dioxide (R-TiO2) as filler was also incorporated to improve the thermal properties of the PLA. 10wt% ENR with epoxidation contents of 25 mol% (ENR25) and 50 mol% (ENR50) and various R-TiO2contents (0-10 phr)were compounded with PLA by using a twin-screw extruder at 155-165°C and a rotor speed of 40 rpm. The pellets of blends were then formed a thin film using a cast film extruder machine and cooled down under air flow. Thermal and mechanical properties and morphology of PLA/ENR/R-TiO2thin film were investigated. The crystallinity of PLA was found to increase with addition of ENR. The mechanical properties of thin film showed that the ENR50 enhanced the elongation but reduced the tensile strength of PLA with addition of R-TiO2at 5 and 10 phr, respectively. The TGA indicated that the addition of 10 phr R-TiO2increased in the decomposition temperature at 5% weight loss (Td5%) of PLA/ENR film. Thus the thermal stability of PLA/ENR50 was found to improve with addition of R-TiO2. From morphology study, the ENR50 phase showed a good dispersion in the PLA matrix. In conclusion, the addition of ENR and R-TiO2was found to enhance both toughness and thermal stability of PLA.

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