scholarly journals The Blending of EPDM/NR with Maleic Anhydride as Compatibilizer: Comparing the Effect of Accelerators on Cure Characteristic and Mechanical Properties

2019 ◽  
Vol 19 (1) ◽  
pp. 106
Author(s):  
Hesty Eka Mayasari ◽  
Ike Setyorini ◽  
Arum Yuniari
Keyword(s):  
Mechanical Properties ◽  
Maleic Anhydride ◽  
Crosslink Density ◽  
Testing Machine ◽  
Cure Rate ◽  
Tensile Testing Machine ◽  
Aging Resistance ◽  
Sem Micrograph ◽  
Cure Characteristic ◽  
Accelerator System

The blending of ethylene propylene diene monomer/natural rubber (EPDM/NR) needs much attention because of their incompatibility. In this work, the influence of accelerator type on cure characteristics and mechanical properties of 60/40 EPDM/NR blend was investigated. The compounds were prepared by controlling the migration of curative and using maleic anhydride as the compatibilizer. Three types of accelerators were studied: 2,2-dithiobis(benzothiazole) (MBTS), the combination of MBTS and tetramethyl thiuram disulfide (TMTD), and n-tert-butyl-2-benzothiazolesulfenamide (TBBS). The cure characteristic, mechanical properties, and morphology of the composites had been investigated by rheometer, tensile testing machine, hardness durometer and scanning electron microscope (SEM). Blending of EPDM/NR with various accelerator gave different composite characteristics. MBTS, used in single or binary accelerator system, provided good mechanical properties. TBBS gave the longest scorch time, the lowest crosslink density and poor mechanical properties, except tear strength. Binary accelerator, MBTS/TMTD, provided the lowest processing time and the highest cure rate, but not significantly different from MBTS. Binary accelerator gives the best aging resistance and compatibility blend. These results correspond well with SEM micrograph. From the study, it can be concluded that binary accelerator system was the proper accelerator for EPDM/NR blend.

Studies on Nanostructured Polyurethane/Clay Interpenetrating Polymer Networks

2005 ◽  
Vol 475-479 ◽  
pp. 1001-1004
Author(s):  
Ninglin Zhou ◽  
Xiao Xian Xia ◽  
Li Li ◽  
Shao Hua Wei ◽  
Jian Shen
Keyword(s):  
Mechanical Properties ◽  
Polymer Networks ◽  
Testing Machine ◽  
Physical And Mechanical Properties ◽  
Interpenetrating Polymer Networks ◽  
Absorption Properties ◽  
Tensile Testing Machine ◽  
Swelling Agent ◽  
Silicate Layers ◽  
Polyurethane Matrix

A novel exfoliated polyurethane (PU)/clay Interpenetrating Polymer Networks (IPNs) nanocomposite has been synthesized with polyurethane and organoclay. MTPAC is used as swelling agent to treat Na-montmorillonite for forming organoclay. The results indicate that there is very good compatibility between organoclay and PU. Nanoscale silicate dispersion was analyzed by XRD. The mechanical properties of the nanocomposites have been measured by tensile testing machine. The nanocomposites show obviously improved physical and mechanical properties when compared with the pure polymer. Additionally, PU /MTPAC- clay shows lower water absorption properties than pure PU do. In addition, the reinforcing and intercalating mechanism of silicate layers in polyurethane matrix are discussed.

scholarly journals Effect of Er on Microstructure and Mechanical Properties of 5052 Aluminum Alloy with Big Width-To-Thickness Ratio

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 568
Author(s):  
Xinwei She ◽  
Xianquan Jiang ◽  
Bao Qi ◽  
Kang Chen
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Tensile Testing ◽  
Testing Machine ◽  
Thickness Ratio ◽  
Tensile Testing Machine ◽  
Microstructure And Mechanical Properties ◽  
Long Time ◽  
Scanning Electron ◽  
Al Matrix

The effect of Er on microstructure and mechanical properties of the 5052 aluminum alloy with a big width-to-thickness ratio was investigated by a metallurgical microscope, scanning electron microscope and tensile testing machine. The results showed that the precipitates were slightly refined after Er addition and Al3Fe was transformed into Al6Fe and AlEr with/without a small amount of Fe or Si. The effect of Er on grain refinement was related to its content. When Er content was lower or higher than 0.4%, the grain would coarsen. Homogenization could refine the grain by controlling Er content and distribution in the Al matrix. Long time homogenization at high temperature would significantly reduce the strength of the 5052 aluminum alloy and 5052 aluminum alloys with low Er content, but help to improve the plasticity of those with high Er content. The ultimate tensile strength, yield strength and elongation of the as-cast 5052 aluminum alloy were 197 MPa, 117 MPa and 22.5% respectively. The strength was the highest, when Er content was 0.4 wt. % and the elongation was the best at 0.1 wt. % Er content.

HXNBR Coating for Improving Aging Resistance of Natural Rubber Products

2006 ◽  
Vol 79 (4) ◽  
pp. 553-560 ◽  
Author(s):  
Rani Joseph
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Room Temperature ◽  
Oxidative Degradation ◽  
Thin Coating ◽  
Oil Resistance ◽  
Aging Resistance ◽  
Natural Rubber Vulcanizates ◽  
Good Heat ◽  
Accelerator System

Abstract HXNBR (Hydrogenated Carboxylated Nitrile Rubber) has very good heat ageing resistance and oil resistance. A novel accelerator system is designed to bring about the vulcanization of HXNBR at room temperature. The room temperature cured samples showed good mechanical properties equivalent to those of high (150 °C) temperature cured samples. Natural rubber vulcanizates are highly prone to oxidative and ozone degradation. The oil resistance of natural rubber vulcanizates is also very low. The oil resistance, ozone and oxidative degradation resistance of natural rubber vulcanizates are considerably improved by placing a thin coating of HXNBR over it.

Microstructure and Mechanical Properties of Vacuum Sintered Austenitic Stainless Steel Parts

2010 ◽  
Vol 160-162 ◽  
pp. 915-920
Author(s):  
Shao Jiang Lin ◽  
Da Peng Feng ◽  
Qi Nian Shi
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Vickers Hardness ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Testing Machine ◽  
Microstructural Characterization ◽  
Tensile Testing Machine ◽  
Hardness Tester

This work presents the possibility of obtaining high density austenitic stainless steel parts by powder metallurgy (PM) and sintered in vacuum. Mechanical properties such as tensile strength, yield stress, elongation rate and Vickers hardness were measured by using a tensile testing machine and a Vickers hardness tester at room temperature. Microstructural characterization was performed by means of optical microscopy and scanning electron microscopy (SEM). The effect of sintering temperature on densification and mechanical properties of PM austenitic stainless steel has been investigated. The results show that density and mechanical properties were increased with the increase of sintering temperature, but when the sintering temperature is above 1340 °C, they increased slowly. The highest mechanical properties were obtained when sintering temperature was 1340 °C.

Microstructure and Mechanical Properties of Mg-9Gd-4Y-0.5Zr Alloy

2017 ◽  
Vol 904 ◽  
pp. 15-18
Author(s):  
Bo Bo Meng ◽  
Quan An Li ◽  
Xiao Ya Chen
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Solid Solution ◽  
Tensile Testing ◽  
Treatment Process ◽  
Testing Machine ◽  
Elongation Rate ◽  
Heat Treatment Process ◽  
Tensile Testing Machine ◽  
Microstructure And Mechanical Properties

The effects of heat treatment on microstructure and mechanical properties of Mg-9Gd-4Y-0.5Zr alloy were studied by XRD, OM, SEM and tensile testing machine. The results show that the alloy mainly consists of α-Mg matrix, Mg5Gd and Mg24Y5. Through solid solution and aging heat treatment process, the tensile strength, yield strength and elongation rate respectively achieves 263.1MPa, 235.2MPa and 3.11%.

scholarly journals Improving the shape stability and enhancing the properties of layer dependent material extruded biodegradable polylactic acid for thin implants

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Alper Ekinci ◽  
Xiaoxiao Han ◽  
Andrew Gleadall ◽  
Andrew Allan Johnson
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Polylactic Acid ◽  
Testing Machine ◽  
Degree Of Crystallinity ◽  
Annealed Specimen ◽  
Future Research ◽  
Shape Stability ◽  
Tensile Testing Machine ◽  
Content Type

Purpose This paper aims to establish an appropriate annealing method, which is necessary for shape stability and to evaluate their potential degradation performance of 1-, 3- and 5-layer material extruded polylactic-acid specimens by enhancing their thermal and mechanical properties. Design/methodology/approach The distortion of each layered printed specimen subjected to degradation was calculated in x- and y-direction. Each layered specimen was subjected to annealing at 70°C, 80°C and 90°C for 2 h and at 80°C for 1, 4, 8 and 16 h. Thermal, molecular weight and mechanical properties were calculated using, differential scanning calorimetry, gel permeation chromatography and tensile testing machine, respectively. Findings In the x-direction, distortion was 16.08 mm for one-layer non-annealed printed specimens and decreased by 73% and 83% for 3- and 5-layer, respectively, while each layered non-annealed specimen subjected to degradation at 37°C for one month. Within the outlined study, annealing treatment enhances properties such as the degree of crystallinity (%χ) up to 34%, Young’s modulus (E) by 30% and ultimate tensile strength by 20% compared to the non-annealed specimens. Practical implications The future research accomplishments will be concentrated on the design, development and optimisation of degraded biomedical implants using material extrusion thin films including drug delivery system and fixation plates. Originality/value The printed thin specimens subjected to degradation were investigated. This research developed a new understanding of the effect of the annealing temperature and time on the mechanical, thermal and molecular weight properties for each layered specimen.

Reinforcement of Ethylene Vinyl Acetate with Carbon Black/Silica Hybrid Filler Composites

2016 ◽  
Vol 852 ◽  
pp. 16-22
Author(s):  
S. Vishvanathperumal ◽  
S. Gopalakannan
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Vinyl Acetate ◽  
Abrasion Resistance ◽  
Crosslink Density ◽  
Testing Machine ◽  
Ethylene Vinyl Acetate ◽  
Hybrid Filler ◽  
Tear Strength ◽  
Silica Hybrid

Carbon black and silica have been used as the main reinforcing fillers that increase the usefulness of rubbers. In this work the effect of carbon black (high abrasion furnace)/silica hybrid fillers on the mechanical properties, crosslink density and morphological behaviour of ethylene vinyl acetate (EVA) was investigated. EVA reinforced with 0/50, 10/40, 20/30, 30/20, 40/10 and 50/0 phr of carbon black (CB)/silica hybrid filler. The total hybrid filler is kept constant at 50 phr (parts per hundred rubbers) and six different compounds were prepared. EVA, CB and silica followed by compounding on a two roll mill and molding at 180°C and 20 megapascal (MPa) pressure. The mechanical properties such as tensile & tear strength, elongation at break and 100% modulus have been measured at 23°C on universal testing machine. Abrasion resistance, hardness and rebound resilience are studied using DIN abrader, Shore A durometer and vertical rebound resilience respectively. The tensile strength, modulus, tear strength, abrasion resistance, hardness and crosslink density increased with the CB filler content in hybrid filler, reached the maximum value at 50 phr of high abrasion furnace carbon black. Morphological properties of composites were evaluated by scanning electron microscopy analysis.

Effect of Coarse-Grained Ring on Mechanical Properties and Cutting Performance of 2011 Aluminum Alloy Extruded Bar

2021 ◽  
Vol 1035 ◽  
pp. 114-118
Author(s):  
Chang Liang Shi ◽  
Yan Ping Niu ◽  
Yi Min Lin ◽  
Quan Hu ◽  
Xin Zhang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Aluminum Alloy ◽  
Tensile Testing ◽  
High Speed ◽  
Testing Machine ◽  
Eutectic Phase ◽  
Cutting Performance ◽  
Coarse Grained ◽  
Tensile Testing Machine

The effects of coarse-grained ring on the mechanical properties and cutting performance of 2011 aluminum alloy extruded bars were studied by metallographic microscope, scanning electron microscope, tensile testing machine and high-speed lathe. The results show that the microstructure of aluminum alloy extruded bar was composed of α-Al phase, Al7Cu2Fe phase, CuAl2 phase and SnBi eutectic phase. There was a coarse-grained ring in the aluminum alloy extruded bar. The coarse-grained ring reduced the mechanical properties and cutting performance of the aluminum alloy extruded bar. The aluminum alloy extruded bar with a diameter of 30 mm had a coarse-grained ring depth of 9 mm and lower mechanical properties, whose the tensile strength was 287.9 MPa, the elongation was 17%, the cutting performance was poor and the chips were long. The aluminum alloy extruded bar with a diameter of 40 mm had a coarse-grained ring depth of 1 mm, higher mechanical properties and better cutting performance, whose the tensile strength was 394.5 MPa, the elongation was 23.5%, the chips were fine and uniform.

Novel preparation method and the characterization of polyurethane-acrylate/ nano-SiO2 emulsions

2018 ◽  
Vol 25 (3) ◽  
pp. 603-610 ◽  
Author(s):  
Chen Guangmei ◽  
Wu Lixia ◽  
Xu Jiahao ◽  
Xu Gewen ◽  
Huang Yiping
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Mass Loss Rate ◽  
Sol Gel ◽  
Testing Machine ◽  
Particle Diameter ◽  
Particle Morphology ◽  
Thermal Mass ◽  
Tensile Testing Machine ◽  
Polyurethane Acrylate

Abstract Polyurethane-acrylate/SiO2 composite (SPUA) emulsions were synthesized by in situ polymerization accompanying the sol-gel process, in which the hydrolysis reaction and polymerization of monomers could be accomplished at the same time. The particle morphology of the SPUA emulsions was observed by scanning electron microscopy and transmission electron microscopy. The particle diameter was measured on a laser particle size analyzer. The molecular structure of the copolymers was characterized by Fourier transform infrared spectrometer (FTIR). Furthermore, tensile testing machine, Shore durometer, and thermogravimetric analyzer were used to investigate the mechanical properties, hardness, and thermal properties. The results indicated that, by increasing the mass fraction of tetraethyl orthosilicate (TEOS), the mechanical properties of the films were improved remarkably. When the weight % of TEOS was 8% in the SPUA emulsion, the water absorption of obtained film was 2.1%, the tensile strength was 16.8 MPa, the shore hardness was 94, and the temperature for the maximal thermal mass-loss rate was 416°C.

Influence of Service Time on the Microstructure and High Temperature Mechanical Properties of T23 Boiler Tube

2017 ◽  
Vol 898 ◽  
pp. 711-718 ◽  
Author(s):  
Cheng He ◽  
Bao Liang Shi ◽  
Wen Sheng Li ◽  
Jian Ping Zhao ◽  
Kai Xu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
High Temperature ◽  
Service Time ◽  
Testing Machine ◽  
Tensile Testing Machine ◽  
Time Service ◽  
High Temperature Mechanical Properties ◽  
The Matrix ◽  
Long Time

The influence of long time service on the microstructure and high temperature mechanical properties of T23 steel was studied by optical microscopy, scanning electron microscopy, transmission electron microscopy and tensile testing machine. Results showed that lathy bainite ferrite disappears with the increasing service time, both the size and number of the carbides increases, and M23C6 carbides transform into M6C carbides rich in W element. The service process also has a significant influence on the recovery. Sub-grains were found at the grain boundaries with little dislocations in the matrix after 27448 h service time. After running for 27448 h the microstructure degradation of T23 steel is serious. High temperature tensile properties of T23 are closely related to the alloy aging degree. The reasons for the decrease of high temperature mechanical properties after long time service included microstructure degradations such as the increase of both the size and quantity of M23C6 carbides, the transformation of M23C6 to M6C, the desolution of Cr,W,and Mo elements, the decrease of the dislocation density and the occurrence of the sub-grains.

Sign in / Sign up

Export Citation Format

Share Document