scholarly journals Impacts of Modified Graphite Oxide on Crystallization, Thermal and Mechanical Properties of Polybutylene Terephthalate

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2431
Author(s):  
Hongyan Li ◽  
Zhijun Wei

In this study, the surface modification on graphene oxide (GO) was performed using octadecylamine (ODA). Furthermore, polybutylene terephthalate/GO (PBT/GO) composites were prepared to elucidate the role of GO surface modification on the mechanical performance, thermal stability and crystallization behavior. Results of Fourier transform infrared spectra (FT-IR), Raman spectrum, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM) revealed that ODA was successfully grafted on GO. Differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), tensile test, Izod impact strength test and TGA were carried out on the PBT/GO composites. Results indicated that the addition of raw GO can enhance the crystallization temperature and degree of crystallinity and can slightly improve the thermal stability and tensile strength of the composites. However, the impact strength and elongation at break were seriously decreased owing to the poor compatibility between the GO and PBT matrix. Once the modified GO was added, the crystallization temperature and degree of crystallinity were greatly increased. The tensile strength increased greatly while the elongation at break and Izod impact strength were efficiently maintained; these were evidently higher than those of PBT/raw GO. Moreover, thermal stability was greatly enhanced. SEM (scanning electron microscope) observation results on the impact-fractured surface clearly confirmed the improved compatibility between the modified GO and PBT matrix. A related mechanism had been discussed.

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Ngoc-Thien Tran ◽  
Nga Thi-Hong Pham

Polybutylene terephthalate (PBT) is a brittle polymer with the disadvantage of low impact toughness, so it is not easy to meet the requirements of both high tensile strength, flexural strength, and high impact strength. In this study, PBT/polycarbonate (PC) blends at different ratios of 95/5, 90/10, 85/15, and 80/20 are investigated. Tensile strength, flexural strength, and unnotched Izod impact strength are studied according to the ASTM D638, ASTM D790, and ASTM D256 standards. The results show that tensile strength, which increased with increasing PC content, is 53.00, 62.34, 60.59, 62.98, and 64.46 MPa for 0, 5, 10, 15, and 20% PC samples. Flexural strength and elastic flexural testing of PBT/PC blends are higher than neat PBT. In addition, the unnotched Izod impact strength of PBT/PC is also higher than PBT. However, when PC content increases, impact strength tends to decrease. Impact strength is 44.82, 80.46, 68.82, 50.45, and 48.05 kJ/m2 corresponds to 0, 5, 10, 15, and 20% PC, in which 5% PC sample is twice as high as the impact strength of PBT. Microstructure of the blends has shown that PC has become dispersed phase in PBT matrix. The size and quantity of dispersed PC particles increase with increasing PC rate in the blend. Thus, when adding PC, PBT/PC all meet the requirements of high tensile strength, flexural strength, and high impact strength. The PBT/5% PC model gives the highest impact strength while still ensuring durability, which potential application for making car door handles.


2020 ◽  
Vol 845 ◽  
pp. 39-44
Author(s):  
Woraporn Kiwjaroun ◽  
Saowaroj Chuayjuljit ◽  
Phasawat Chaiwutthinan ◽  
Anyaporn Boonmahitthisud

The aim of this study is to prepare green composites from poly (lactic acid) (PLA) and in-house epoxidized natural rubber (ENR) with coir fibers (CFs). In-house ENR with medium epoxidation degree (about 35 mole% epoxidation) was first prepared via ‘in situ’ epoxidation of natural rubber latex. PLA was melt-mixed with three loadings (10, 20 and 30 wt%) of ENR on a twin-screw extruder, followed by injection molding to observe their mechanical properties (impact strength, tensile strength, Young’s modulus and elongation at break) and thermal stability. The results showed that the addition of the ENR enhanced the impact strength and elongation at break, but deteriorated tensile strength, Young’s modulus and thermal stability of the blends. From mechanical properties consideration, the 90/10 PLA/ENR blend was selected for preparing green composites with different amounts of CFs (5, 10 and 20 phr). It was found that the incorporation of CFs improved tensile strength and Young’s modulus. However, the impact strength, elongation at break and thermal stability of the green composites decreased as compared to those of the neat 90/10 PLA/ENR blend.


2019 ◽  
Vol 947 ◽  
pp. 77-81
Author(s):  
Natsuda Palawat ◽  
Phasawat Chaiwutthinan ◽  
Sarintorn Limpanart ◽  
Amnouy Larpkasemsuk ◽  
Anyaporn Boonmahitthisud

The aim of this study is to improve the physical properties of poly(lactic acid) (PLA) by incorporating thermoplastic polyurethane (TPU), organo-montmorillonite (OMMT) and/or nanosilica (nSiO2). PLA was first melt mixed with five loadings of TPU (10–50 wt%) on a twin-screw extruder, followed by injection molding. The addition of TPU was found to increase the impact strength, elongation at break and thermal stability of the blends, but decrease the tensile strength and Young’s modulus. Based on a better combination of the mechanical properties, the 70/30 (w/w) PLA/TPU blend was selected for preparing both single and hybrid nanocomposites with a fix total nanofiller content of 5 parts per hundred of resin (phr), and the OMMT/nSiO2 weight ratios were 5/0, 2/3, 3/2 and 0/5 (phr/phr). The Young’s modulus and thermal stability of the nanocomposites were all higher than those of the neat 70/30 PLA/TPU blend, but at the expense of reducing the tensile strength, elongation at break and impact strength. However, all the nanocomposites exhibited higher impact strength and Young’s modulus than the neat PLA. Among the four nanocomposites, a single-filler nanocomposite containing 5 phr nSiO2 exhibited the highest impact strength and thermal stability, indicating that there was no synergistic effect of the two nanofillers on the investigated physical properties. However, the hybrid nanocomposite containing 2/3 (phr/phr) OMMT/nSiO2 possessed a compromise in the tensile properties.


2013 ◽  
Vol 575-576 ◽  
pp. 203-208
Author(s):  
Hong Xing Xu ◽  
Xin Hua Yuan ◽  
En Bo Zhu ◽  
Shuang Lian Li ◽  
Ling Chen ◽  
...  

The polytetrafluoroethylene (PTFE) matrix composites which filled with polyphenylene sulfide (PPS) fiber, poly-p-phenelenferephthalamide (PPTA) fibre or glass fiber (GF)) and graphite at various mass fractions were prepared by the processes of mechanical blending, compression molding and sintering. The mechanical properties of the composites, such as tensile strength, impact strength and hardness were investigated. The results show that tensile strength and elongation at break markedly decrease but elasticity increases by filling with fibers. Impact strength decreases by filling with PPS and GF, and the composite displays brittle characteristic. However, the impact strength rapidly increases by filling with PPTA fiber. Hardness increases with the fibers content increases, and decreases with graphite content increases. Filling graphite into PTFE has light effect on the impact and tensile strength of composites. The tribological properties of the composites were investigated on M-2000 wear tester at dry friction condition. The wear mechanism was also discussed and the wear surfaces were examined by SEM. The result indicates that fibers which diffused in PTFE matrix wind with PTFE molecule chain, and then form grid structure. The load-bearing capacity of composites can be obviously enhanced and the trend of block fragmentations slide is inhibited, so that the tribological properties are improved markedly.


2021 ◽  
Vol 877 ◽  
pp. 3-8
Author(s):  
Prathumrat Nuyang ◽  
Atiwat Wiriya-Amornchai ◽  
Watthanaphon Cheewawuttipong

The effect of compatibilizer agent was studied when adding Aluminum fine powder (Al) to reinforce in Polypropylene (PP) by compared between polymer matrix composites (PMCs) and PMCs added Polypropylene graft maleic anhydride (PP-g-MAH).The average particle size of the aluminum fine powder was around 75 μm filled in polypropylene with different proportions of 2.5, 5, 7.5 and 10wt%. PMCs were prepared using the internal mixer. The results found that when the amount of aluminum fine powder increased, the mechanical properties had changed, i.e., tensile strength, and Young’s Modulus increased, while the impact strength and elongation at break decreased. But, when adding compatibilizer 1wt% it was found that the trend of tensile strength, and Young’s Modulus increased that compared with non-compatibilizer, but the impact strength and elongation at break decreased. The part of the morphology of PMCs with non-compatibilizer was found that the particle of aluminum fine powder dispersed in the matrix phase, but there were many microvoids between filler and matrix. But, PMCs with compatibilizer caused the microvoids between filler and matrix to be reduced.


2013 ◽  
Vol 834-836 ◽  
pp. 237-240 ◽  
Author(s):  
Kanyakorn Pawarangkool ◽  
Wirunya Keawwattana

In this work, hydroxyapatite (HAp) was produced from crocodile bones by thermal process at 900°C. X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR) and Scanning electron microscope (SEM) were used to characterize the obtained HAp. Polylactic acid (PLA)/HAp composites were prepared by melt blending as follows: 95/5, 90/10 and 85/15 (weight ratio). The effect of the amount of HAp on the mechanical properties including tensile strength, modulus, elongation at break and impact strength of PLA/HAp composites was undertaken. It was found that tensile strength and elongation at break of the composites decreased with an increase of HAp content, while modulus and impact strength showed no significant effect.


2012 ◽  
Vol 488-489 ◽  
pp. 62-66
Author(s):  
Jareenuch Rojsatean ◽  
Supakij Suttireungwong ◽  
Manus Seadan

The blend of poly(styrene-co-acrylonitrile) (SAN) and natural rubber (NR) is immiscible and incompatible which lead to poor mechanical properties. Many methods can be carried out to improve the compatibility. In this work, the potential of various reactive compatibilizers in SAN and NR blend was explored. The morphological and mechanical properties were compared. The melt blending of SAN and NR were prepared in an internal mixer with various types of reactive agent such as styrene-co-maleic anhydride (SMA), maleic anhydride (MA), peroxide and mixed reactive agents. The morphological textures of the blends were investigated by scanning electron microscope. Mechanical properties including tensile strength, impact strength and elongation at break were measured. The results of morphological observations revealed that SAN/NR blend with reactive agent, the mixture of SMA and MA show the smallest and the most uniform dispersed NR particles, where the size of NR particle is about 1 µm. The mechanical properties of the blends revealed impact strength and elongation at break were increased with addition of reactive agents. SAN/NR blend with the mixture of SMA and MA showed the highest elongation at break but it had lower impact strength than the blend with SMA.


REAKTOR ◽  
2007 ◽  
Vol 11 (2) ◽  
pp. 71
Author(s):  
Bahruddin Bahruddin ◽  
Sumarno Sumarno ◽  
Gede Wibowo ◽  
Nonot Suwarno

Morfologi dan properti campuran (blend) karet alam jenis SIR-20/polypropylene (NR/PP) yang divulkanisasi dinamik dalam internal mixer telah dipelajari. Blend dibuat dengan rasio berat NR/PP 10/90, 20/80, 50/50, 60/40 dan 70/30 dan komposisi sulfur 3 dan 5 phr (per hundred rubber). Proses pencampuran dilakukan pada suhu 180 oC dan kecepatan rotor 60 rpm. Analisa morfologi menggunakan SEM (Scanning Electron Microscope) dan DSC (Differential Scanning Calorimetry). Properti mekanik yang diukur meliputi tensile strength, elongation at break, izod impact, tearing dan hardness, berdasarkan standar ASTM. Didapatkan bahwa peningkatan rasio NR/PP menghasilkan distribusi partikel NR yang makin merata dengan ukuran yang makin kecil. Morfologi blend menunjukkan sistem dua fasa dan vulkanisasi fasa NR terjadi secara parsial dalam matrik PP. Peningkatan rasio NR/PP dan komposisi sulfur dapat meningkatkan properti elongation at break, namun menurunkan properti tensile strength, izod impact, tearing dan hardness. Elongation at break tertinggi yang dapat diperoleh adalah 70% pada rasio blend NR/PP 70/30 dan komposisi sulfur 5 phr.


2020 ◽  
Vol 82 (5) ◽  
Author(s):  
Muhammad Akmal Ahmad Saidi ◽  
Azman Hassan ◽  
Mat Uzir Wahit ◽  
Lai Jau Choy ◽  
Hazleen Anuar

Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and mechanical tests were conducted to characterize the properties of polybutylene terephthalate/polyethylene terephthalate (PBT/PET) blends. PBT and PET were blended at different PBT/PET ratios (80/20, 60/40, 40/60, 20/80) via twin screw extruder prior to injection molding. DSC characterization showed a single glass transition temperature for all PBT/PET blends indicating that the miscibility occurred in the amorphous region. From DMA results, loss modulus and tan δ also showed a single peak for all PBT/PET blends, confirming the DSC results. At room temperature, PBT/PET 20/80 has the highest storage modulus followed by PBT/PET 80/20 blend. PET has higher tensile strength, flexural strength, Young’s and flexural modulus than PBT but lower in elongation at break and impact strength. PBT/PET 80/20 blend has the highest tensile strength, flexural strength, elongation at break, and impact strength compared to other PBT/PET blends. PBT/PET 80/20 blend can be suggested as an optimum formulation with balanced mechanical properties in terms of stiffness and toughness.


2010 ◽  
Vol 13 (1-2) ◽  
pp. 67
Author(s):  
S. Manocha ◽  
Valay Solanki ◽  
Nikesh Patel ◽  
L.M. Manocha

<p>Organically modified nanoclay (cation exchange capacity of 135 to 145 meq/100 g) was used as nanophase reinforcement for fabrication of nylon-6 nanocomposites. The thickness of clay platelets varied form 1.2 nm to 1.3 nm with 3.485 nm as d-spacing. Nylon 6/nanoclay composites were fabricated with loading of 2.5, 5.0 and 10 wt.% nanoclay via direct melt compounding technique using conventional twinscrew extruder. Processing temperature profile from hopper to header was 230-240-245-260 °C and screw speed was maintained at 180 rpm. The nylon 6/clay nanocomposites were characterized for thermal and mechanical properties. The structural properties were characterized by Differential Scanning Calorimeter (DSC) and X-ray diffraction analysis. The tensile fracture morphology was analyzed by using Scanning Electron Microscope (SEM). DSC nonisothermal curves show an increase in the crystallization temperature with increasing degree of crystallinity. The crystallization rate of the nanoclay reinforced nylon 6 composites was found to be significantly faster than that for the pristine nylon 6 and suggests that the layered silicates act as nucleating centers. XRD result shows that addition of nanoclay by this technique favors the formation of γ-crystalline phase in nylon 6/nanoclay composites. Due to this, there is substantial enhancement in the tensile strength and Izod impact strength. A variation from 700 to 971 Kg/cm<sup>2</sup> for tensile strength and from 3.0 to 3.4 Kg.cm/cm of notch for Izod impact strength. The detailed results are presented.</p>


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