scholarly journals Mechanical and Thermal Properties of Poly(urethane urea) Nanocomposites Prepared with Diamine-Modified Laponite

2008 ◽  
Vol 2008 ◽  
pp. 1-9 ◽  
Author(s):  
Joe-Lahai Sormana ◽  
Santanu Chattopadhyay ◽  
J. Carson Meredith
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
Tensile Properties ◽  
Particle Concentration ◽  
Chain Extender ◽  
Mechanical And Thermal Properties ◽  
Elongation At Break ◽  
Hard Domain ◽  
A Chain

Nanocomposites based on segmented poly(urethane urea) were prepared by reacting a poly(diisocyanate) with diamine-modified Laponite-RD nanoparticles that served as a chain extender. The nanocomposites were prepared at a constantNH2to NCO mole ratio of 0.95, while varying the fraction of diamine-modified Laponite relative to the free diamine chain extender. Compared to neat poly(urethane urea), all nanocomposites showed increased tensile strength and elongation at break. As Laponite loading increased, tensile properties passed through a maximum at a particle concentration of 1 mass%, at which a 300% increase in tensile strength and 40% increase in elongation at break were observed. A maximum in urea and urethane hard-domain melting endotherms was also observed at this Laponite loading. Optimal mechanical and thermal properties coincided with a minimum in the size of the inorganic Laponite phase. Nanocomposites containing diamine-modified Laponite had higher tensile strengths than those with nonreactive monoamine-modified Laponite or diamine-modified Cloisite.

Effect of chain extender on the mechanical and thermal resistance properties of polyurethane liners for composite propellants

Polyurethanes ◽  
2016 ◽  
Vol 1 (1) ◽  
Author(s):  
P. Ross ◽  
G. Sevilla ◽  
J. Quagliano
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Chain Extender ◽  
Molecular Structures ◽  
Polymer Chains ◽  
Mechanical And Thermal Properties ◽  
Thermal Changes ◽  
Ft Ir ◽  
Chain Lengths

AbstractPolyurethane formulations utilized as liners for composite propellants were prepared by the reaction of toluene-2,4-diisocyanate (TDI) and isophorone diisocyanate (IPDI) with hydroxyl terminated polybutadiene (HTPB), while polymer chains were further extended with neopentyl glycol diol, NPG triol and two different triols (monoglyceryl ricinoleate, MRG and trimethylolpropane, TMP). Liners were formulated with micronized titanium dioxide mechanically dispersed in hydroxyl-terminated polybutadiene (HTPB). The molecular structures of liners were confirmed by FT-IR. Thermal properties indicated that the nature of chain extender (crosslinker) only slightly affected the temperatures for decomposition of liners. Two main thermal changes were found at 370∘C and another at around 440–500∘C, depending on the chain extender utilized. On the other side, mechanical properties varied within the range of 0,7-1,8 MPa, consistent with this kind of elastomers. Tensile strength at break was only significantly affected with TMP and MRG-chain extended liners at the lowest concentrations tested of 1,3 and 2% (w/w), respectively. However, the behaviour depended on whether TDI or IPDI isocyanate was utilized for curing. TMP 1,3% crosslinked liner cured with TDI had a tensile strength of 1,82MPa whileMRG-crosslinked liner cured with IPDI had a tensile strength of 1,56 MPa. It was observed that at the higher NCO/OH ratios essayed, tensile strength and hardness increased, improving mechanical properties. Our results confirmed that TMP and MRG triols together with NPG diols can be used to tailor mechanical and thermal properties of liners, considering their different hydroxyl functionalities and chain lengths.

Natural Rubber-Whisker Alumina Fiber Composite Materials for Mechanical and Thermal Insulation Applications

2018 ◽  
Vol 789 ◽  
pp. 221-225
Author(s):  
Nattapol Dedruktip ◽  
Wasan Leelawanachai ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Natural Rubber ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Curing Temperature ◽  
Mechanical And Thermal Properties ◽  
Alumina Fiber ◽  
Elongation At Break

Alumina fiber is a ceramic material used as a dispersed phase or filler to reinforce the mechanical and improve thermal properties of natural rubber via vulcanization process at curing temperature 150°C. The amount of alumina fiber added in natural rubber was varied from 0 to 50 phr on 100 phr of natural rubber in a sulfur curing system. Adding 10 phr alumina fiber affects to obtain the best natural rubber composite samples having good mechanical and thermal properties. Tensile strength, elongation at break, Young’s modulus and thermal conductivity of adding 10 phr whisker alumina fiber encoded NR-Al-10 are equal to 14.38±1.95 MPa, 1038.4±41.45%, 545.63±25.67 MPa and 0.2376±0.0003 W/m.K, respectively, better than those of pure natural rubber compounds without adding alumina fiber. Tensile strength, elongation at break, Young’s modulus and thermal conductivity of natural rubber without adding alumina fiber are equal to 14.06±6.03 MPa, 949.41±52.15%, 496.32±8.54 MPa and 0.2500±0.0003 W/m.K, respectively.

Preparation and Properties of Nanocomposites Consist of Carbon Black N220 and Epoxy Resin

2011 ◽  
Vol 308-310 ◽  
pp. 820-823
Author(s):  
Jian Jiao ◽  
Pan Bo Liu ◽  
Liang Zou ◽  
Guang Li Wu
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
Carbon Black ◽  
Epoxy Resin ◽  
Tensile Fracture ◽  
Mechanical And Thermal Properties ◽  
Elongation At Break ◽  
Tensile Fracture Surface ◽  
Mixing Method ◽  
Different Content

The nanometer carbon black (CB) N220 of different content was employed to prepare carbon black N220/epoxy resin (CB N220/EP) composites by filling-mixing method. The structure of CB N220 and its dispersion in epoxy resin were analyzed by TEM and tensile fracture surface of the composites was analyzed by SEM. Experimental results showed that CB N220 was dispersed in epoxy resin homogenously in the form of CB particles and it formed a good interface with epoxy resin in the presence of coupling agent (KH-550). Using of CB N220 enhanced the mechanical and thermal properties of the composites, for tensile strength, elongation at break, impact strength and flexural strength of the composites filled with 2 wt% CB N220 reached a maximum values( 82Mpa、3％、20 KJ•m-2、107Mpa), a rise of 32.3％、39.6％、88.7％、10.3％, respectively, compared to pristine epoxy resin.

scholarly journals EFFECTS OF STARCH-GLYCEROL CONCENTRATION RATIO ON MECHANICAL AND THERMAL PROPERTIES OF CASSAVA STARCH-BASED BIOPLASTICS

2019 ◽  
Vol 20 (4) ◽  
pp. 162
Author(s):  
Akbar Hanif Dawam Abdullah ◽  
Oceu Dwi Putri ◽  
Winda Windi Sugandi
Keyword(s):  
Contact Angle ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Concentration Ratio ◽  
Surface Hydrophobicity ◽  
Cassava Starch ◽  
Mechanical And Thermal Properties ◽  
Glycerol Concentration ◽  
Water Contact ◽  
Elongation At Break

This study aimed to investigate the effects of different starch-glycerol concentration ratio on mechanical and thermal properties of cassava starch bioplastics. Bioplastics were prepared by mixing starch with glycerol at different starch-glycerol w/w ratio (2.5:1, 2.75:1, 3:1 and 3.5:1). Mechanical properties was evaluated by measuring tensile strength and elongation at break where thermal properties was assessed by thermogravimetric analysis to determine the glass transition temperature (Tg), melting temperature (Tm) and melting enthalpy (ΔHm) of bioplastics. Microstructure and chemical interactions in bioplastics were evaluated by SEM and FTIR. The surface hydrophobicity was determined by measuring the water contact angle. The increase of starch-glycerol concentration in bioplastics formed rough surface where the interaction of glycerol and starch molecules mainly occurred through hydrogen bonds. It also formed stronger and more rigid structure with the increase in tensile strength from 1.90 MPa to 2.47 MPa and the decrease in elongation at break from 8.55% to 5.92%. Furthermore, the increase of starch-glycerol concentration increased Tg from 37.5 ºC to 38.6 ºC, Tm from 96.3 ºC to 120.7 ºC and ΔHm from 100.4 J/g to 155 J/g. Moreover, surface contact angle of bioplastics was increased from 40.6º to 60.2º with the increase of starch-glycerol concentration ratio.

Comparison between Mechanical and Thermal Properties of Polylactic Acid and Natural Rubber Blend Using Calcium Carbonate and Vetiver Grass Fiber as Fillers

2011 ◽  
Vol 410 ◽  
pp. 59-62 ◽  
Author(s):  
Punmanee Juntuek ◽  
Chaiwat Ruksakulpiwat ◽  
Pranee Chumsamrong ◽  
Yupaporn Ruksakulpiwat
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Calcium Carbonate ◽  
Impact Strength ◽  
Natural Rubber ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Vetiver Grass ◽  
Elongation At Break

From our previous study, natural rubber (NR) was used to improve toughness of poly (lactic acid) (PLA). Impact strength and elongation at break of PLA was increased when adding NR. Moreover, by using NR-g-GMA as compatibilizer for PLA and NR blend, impact strength and elongation at break was improved. However, tensile strength and modulus of PLA/NR blend with and without NR-g-GMA were decreased. In this study, calcium carbonate (CaCO3) and vetiver grass fiber were used as fillers in PLA/NR blend. With the addition of CaCO3 into PLA/NR blend with NR-g-GMA, impact strength and modulus of the composite were further increased with a loss in tensile strength. In contrast, the addition of vetiver grass fiber into PLA/NR blend with NR-g-GMA led to an increase in tensile strength and modulus and a decrease in impact strength and elongation at break. The onset degradation temperatures of PLA composites were lower than that of PLA and PLA/NR blend.

Processing, Thermal Behavior and Tensile Properties of PLA/Thermoplastic Starch/Montmorillonite Nanocomposites

2013 ◽  
Vol 684 ◽  
pp. 75-79
Author(s):  
Esmat Jalalvandi ◽  
Taravat Ghanbari ◽  
Hossein Cherghibidsorkhi ◽  
Ehsan Zeimaran ◽  
Hamid Ilbeygi
Keyword(s):  
Tensile Strength ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Thermal Behavior ◽  
Tensile Properties ◽  
Thermoplastic Starch ◽  
Screw Extruder ◽  
Elongation At Break ◽  
Twin Screw

Thermoplastic starch, polylactic acid glycerol and maleic anhydride (MA) were compounded with natural montmorillonite (MMT) through a twin screw extruder to investigate the effects of different loading of MMT on tensile properties and thermal behavior of the nanocomposites. Tensile results showed an increased in modulus, tensile strength and elongation at break. However, beyond 3phr of MMT the modulus of samples decreased because the MMT particles agglomerated. The thermal properties were characterized by using differential scanning calorimeter (DSC). The results showed that MMT increased melting temperature and crystallization temperature of matrix but reduction in glass transition temperature was observed.

Study on the Properties of DSM SOMOS 11120 Type Photosensitive Resin for Stereolithography Materials

2011 ◽  
Vol 233-235 ◽  
pp. 194-197 ◽  
Author(s):  
Bi Wu Huang ◽  
Zi Xiang Weng ◽  
Wei Sun
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Functional Groups ◽  
Tensile Modulus ◽  
Mechanical And Thermal Properties ◽  
Elongation At Break ◽  
Photosensitive Resin

DSM SOMOS 11120 type photosensitive resin possessed the biggest consumption for the stereolithography fabricated parts. Therefore the further research on DSM SOMOS 11120 type photosensitive resin was very meaningful and valuable. In the paper, DSM SOMOS 11120 type photosensitive resin was characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy, showing the presence of epoxy and acrylic functional groups. The viscosity of the 11120 type photosensitive resin were also determined, indicating that the viscosity at 30°C was 260mPa.s. Meanwhile, the mechanical and thermal properties of its UV-cured specimens were evaluated, testing that the tensile strength was 50.8MPa, the tensile modulus was 2659MPa, the elongation at break was 11.3%, and the glass transistion temperature was 49°C.

Preparation and characterization of biodegradable blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and poly(butylene adipate-co-terephthalate)

2016 ◽  
Vol 36 (5) ◽  
pp. 473-480 ◽  
Author(s):  
Min Zhang ◽  
Xiaoqian Diao ◽  
Yujuan Jin ◽  
Yunxuan Weng
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Crystallization Temperature ◽  
Molecular Interaction ◽  
Mechanical And Thermal Properties ◽  
Elongation At Break ◽  
Tear Strength ◽  
Biodegradable Blends

Abstract Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) was blended with poly(butylene adipate-co-terephthalate) (PBAT) by extrusion at different weight ratios (PHBH/PBAT: 100:0, 80:20, 60:40, 50:50, 40:60, 20:80 and 0:100). Films were then prepared from the blends and characterized in terms of their morphological, rheological, mechanical and thermal properties. The morphological and rheological results indicated that PHBH/PBAT blends are immiscible but exhibit possible molecular interaction. The crystallization temperature of PHBH in the blends decreased, indicating that the addition of PBAT inhibited the crystallization of PHBH. Blending PBAT with PHBH improved the processability compared with that of pure polymers. The mechanical properties, including tensile strength, elongation at break and tear strength, increased with increasing PBAT content. The PHBH/PBAT 20:80 blend exhibited significantly improved mechanical properties, which was due to the reinforcing and toughening effect of the finely dispersed PHBH phase.

Investigation of multiple-stresses on mechanical and thermal properties of 9000 h Aged RTV-SiR composites for high-voltage insulation

2020 ◽  
pp. 009524432095358
Author(s):  
Atif Mahmood ◽  
Muhammad Amin ◽  
Hidayatullah Khan ◽  
Israrullah ◽  
Fazal Muhammad ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
High Voltage ◽  
Thermal Characteristics ◽  
Superior Performance ◽  
Maximum Deviation ◽  
Mechanical And Thermal Properties ◽  
Multiple Stresses ◽  
Elongation At Break ◽  
Minimum Change

Due to many advantages, polymer composite insulators have been extensively used for high-voltage (HV) transmission lines and substation insulations. The in-service operation, various environmental and electrical stresses degrade their mechanical and thermal characteristics. In this study, nine thousand-hour (9000 h) multi-stress (HV, heat, acid rain, salt fog, ultraviolet (UV) radiation, and humidity) accelerated lab-weathering evaluation of alumina-trihydrate (ATH) and silicon dioxide (SiO2) filled silicone rubber (SiR) composites were utilized. Moreover, to quantify the influence of multiple stresses over 9000 h lab-aging, the tensile strength, elongation at break, hardness, and thermal properties were evaluated and compared with the characterization results of neat (un-aged) composites. Winter and summer-aging cycles were designed in accordance with the actual service environment of Islamabad (Pakistan). Mechanical results of SiR blends showed a decrease in the tensile strength and the elongation at break (EAB), whereas the hardness increased over 9000 h lab-aging. The maximum deviation of ∼57.1% in tensile strength was found for hybrid samples (micro-ATH+ nano-Silica blend: SMNC), whereas the minimum change of ∼25.73% was exhibited by micro-silica-filled SiR specimen SMC3. Compared to neat blends, the maximum variation in EAB was ∼61% for a neat sample (SiR), whereas minimum change was noticed for SMC2 (of ∼31%) over 9000 h lab-aging. Additionally, after 9000 h lab-aging, the maximum (of ∼79.6%) and minimum (of ∼24.4%) variation in hardness was found for hybrid and SiR samples, respectively. Moreover, thermogravimetric (TGA) analysis showed that relative to neat samples, the thermal stability of aged specimens was decreased over weathering. Among aged specimens, only ATH filled samples (SMC1, SMC2) exhibited superior performance for a given temperature range (from 0°C to 900°C) by leaving a higher residual weight of ∼68.6% for SMC2. Hence to simulate and quantify the influence of environmental stresses over insulant performance, accelerated lab weathering can be adopted as an efficient tool.

scholarly journals Exploring the Effects of Fermented Chitin Nanowhiskers on Tensile and Thermal Properties of Poly(ethylene glycol) modified Polylactic Acid Nanocomposites

2021 ◽  
Vol 17 (2) ◽  
pp. 154-165
Author(s):  
Syazeven Effatin Azma Mohd Asri ◽  
Zainoha Zakaria ◽  
Azman Hassan ◽  
Mohamad Haafiz Mohamad Kassim ◽  
Reza Arjmandi
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
Tensile Properties ◽  
Tensile Modulus ◽  
Polyethylene Glycols ◽  
Poly Lactic Acid ◽  
Poly Ethylene Glycol ◽  
Elongation At Break ◽  
Chitin Nanowhiskers ◽  
Poly Ethylene

The incorporation of fermented chitin nanowhiskers (FCHW) into poly(lactic acid) (PLA) increased the tensile modulus and strength of PLA at the expense of ductility. The brittleness of PLA can be overcome with the use of plasticizer such as polyethylene glycols (PEG). The objective of this study is to investigate the effect of FCHW on the tensile and thermal properties PLA incorporated with PEG as plasticizer (PLA/PEG). PLA/PEG and FCHW reinforced PLA/PEG nanocomposites were prepared using solution mixing technique. Thermogravimetric analysis (TGA) was used to determine the thermal properties while tensile properties were determined from the tensile test. The incorporation of PEG successfully increased the ductility and tensile strength of PLA at the expense of modulus. Based on the tensile properties, 5 phr PEG was chosen for further investigation on the effect of FCHW on PEG modified PLA. Incorporation of 1 phr FCHW PLA/PEG increased the tensile strength and Young’s modulus. However, the tensile strength decreased with further addition of FCHW. The elongation at break of PLA/PEG decreased drastically with the incorporation of 1 phr FCHW and decreased gradually with further increase of FCHW. The thermal stability from TGA of FCHW reinforced PLA/PEG nanocomposites at 5 phr FCHW content was observed to be significantly higher compared to PLA/PEG, as indicated by T20 and Tmax.

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