Effect of OMMT reinforcement on morphology and rheology properties of polyurethane copolymer nanocomposites

2021 ◽  
pp. 009524432110061
Author(s):  
Muayad Albozahid ◽  
Haneen Zuhair Naji ◽  
Zoalfokkar Kareem Alobad ◽  
Alberto Saiani
Keyword(s):  
Structural Features ◽  
X Ray Diffraction ◽  
Thermal Transitions ◽  
Scanning Calorimetry ◽  
Melt Temperature ◽  
Rheological Analysis ◽  
Moulding Process ◽  
Injection Moulding Process ◽  
A Chain

The remarkable structural features of organic modified montmorillonite particles (OMMT) enable them to complete their important role in enhancing different properties of polyurethane copolymer with 75 wt.% hard segments (PUC/75). Based on the melt intercalation approach, various amounts of OMMT were incorporated into PUC/75 solution followed by the injection moulding process. It is essential to mention that the synthesized PUC/75 in this work relied on using 1,5-Pentanediol as a chain extender in order to produce a long-term and thermal-stable PUC successfully. The effect of incorporating various loading of OMMT on rheological properties of neat PUC/75 and its nanocomposites was investigated. The structure of PUC/OMMT was studied using X-ray diffraction (XRD) and scanning electron microscopy. Additionally, differential scanning calorimetry (DSC) thermograms were utilized to investigate OMMT effect on the thermal transitions and crystallinity of resultant PUC nanocomposites. Interestingly, the dynamic rheological analysis exhibited a remarkable increase in melt rheology behaviour with increasing OMMT loading compared to neat PUC/75. This could imply a good interaction between the functional group on the surface of OMMT and PUC/75 domains; particularly hard domains, herein the DSC results showed moderate improvement in melt temperature (Tm) of PUC/OMMT nanocomposite. However, a decline in crystalline temperature (Tc) was also seen due to aggregation of OMMT, especially at higher OMMT loading. While XRD results exhibited a slight shifting in crystalline peaks of PUC nanocomposites relative to neat PUC/75.

scholarly journals Rheological, Thermal, Superficial, and Morphological Properties of Thermoplastic Achira Starch Modified with Lactic Acid and Oleic Acid

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4433 ◽  
Author(s):  
Carolina Caicedo ◽  
Rocío Yaneli Aguirre Loredo ◽  
Abril Fonseca García ◽  
Omar Hernán Ossa ◽  
Aldo Vázquez Arce ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Oleic Acid ◽  
Complex Viscosity ◽  
Thermoplastic Starch ◽  
Residual Energy ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Rheological Analysis ◽  
Acid Agent

The modification of achira starch a thermoplastic biopolymer is shown. Glycerol and sorbitol, common plasticizers, were used in the molten state with organic acids such as oleic acid and lactic acid obtaining thermodynamically more stable products. The proportion of starch:plasticizer was 70:30, and the acid agent was added in portions from 3%, 6%, and 9% by weight. These mixtures were obtained in a torque rheometer for 10 min at 130 °C. The lactic acid managed to efficiently promote the gelatinization process by increasing the available polar sites towards the surface of the material; as a result, there were lower values in the contact angle, these results were corroborated with the analysis performed by differential scanning calorimetry and X-ray diffraction. The results derived from oscillatory rheological analysis had a viscous behavior in the thermoplastic starch samples and with the presence of acids; this behavior favors the transitions from viscous to elastic. The mixture of sorbitol or glycerol with lactic acid promoted lower values of the loss module, the storage module, and the complex viscosity, which means lower residual energy in the transition of the viscous state to the elastic state; this allows the compounds to be scaled to conventional polymer transformation processes.

Inosose-Flüssigkristalle / Inosose Liquid Crystals

1990 ◽  
Vol 45 (7) ◽  
pp. 1084-1090 ◽  
Author(s):  
Klaus Praefcke ◽  
Bernd Kohne ◽  
Andreas Eckert ◽  
Joachim Hempel
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
High Temperature ◽  
Liquid Crystalline ◽  
Structural Features ◽  
Lyotropic Liquid Crystal ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Alkyl Chains

Six S,S-dialkyl acetals 2a-f of inosose (1), tripodal in structure, have been synthesized, characterized and investigated by optical microscopy and differential scanning calorimetry (d.s.c.). The four S,S-acetals 2c-f with sufficiently long alkyl chains are thermotropic liquid crystalline; 2 e and 2 f are even dithermomesomorphic. Each of these four inosose derivatives 2c-f exhibits monotropically a most likely cubic mesophase (MI); in addition 2e and 2f show enantiotropically a hexagonal mesophase (Hx) with a non-covalent, supramolecular H-bridge architecture. Whereas the nature of the optically isotropic mesophase MI needs further clarification the stable high temperature mesophase Hx of 2 e and 2 f has been established by a miscibility test using a sugar S,S-dialkyl acetal also tripodal in structure and with a Hx phase proved by X-ray diffraction, but in contrast to 2 with an acyclic hydrophilic part. Similarities of structural features between the Hx-phases of 2e and 2f as well as of other thermotropic and lyotropic liquid crystal systems are discussed briefly.

scholarly journals Influence of 1D and 2D Carbon Fillers and Their Functionalisation on Crystallisation and Thermomechanical Properties of Injection Moulded Nylon 6,6 Nanocomposites

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Fabiola Navarro-Pardo ◽  
Ana L. Martínez-Hernández ◽  
Victor M. Castaño ◽  
José L. Rivera-Armenta ◽  
Francisco J. Medellín-Rodríguez ◽  
...  
Keyword(s):  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Reduced Form ◽  
Scanning Calorimetry ◽  
Graphene Nanocomposites ◽  
Moulding Process ◽  
Nylon 6,6 ◽  
Injection Moulding Process ◽  
The One ◽  
Carbon Fillers

Carbon nanotubes (CNTs) and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation. Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs.

Investigating the Effects of Injection Moulding Process Parameters on Multiple Tensile Characteristics of Plastic Spur Gear via Experimental Approach

2013 ◽  
Vol 748 ◽  
pp. 544-548 ◽  
Author(s):  
Nik Mizamzul Mehat ◽  
Shahrul Kamaruddin ◽  
Abdul Rahim Othman
Keyword(s):  
Process Parameters ◽  
Injection Moulding ◽  
Experimental Approach ◽  
Low Cost ◽  
Spur Gear ◽  
Melt Temperature ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process ◽  
State Of Tension

This paper presents the original development of an experimental approach in studying the multiple tensile characterizations as key quality characteristics for several different plastic gear materials related to various parameters in injection moulding process. In this study, emphases are given on a new low-cost mechanism for the testing of the injection moulded plastic spur gear specimens with various teeth module. The testing fixture are developed and validated to provide uniform state of tension with series of plastic gear specimens produced in accordance with the systematically designed of experiment. The effects of changes in the process parameters including melt temperature, packing pressure, packing time and cooling time at three different levels on the elongation at break and ultimate strength of plastic gear is evaluated and studied through the proposed experimental approach.

scholarly journals New thermoplastic poly(carbonate-urethane) elastomers

2011 ◽  
Vol 13 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Anna Kultys ◽  
Magdalena Rogulska
Keyword(s):  
Soft Segment ◽  
Tensile Tests ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Melt Polymerization ◽  
Atomic Force ◽  
Amorphous Structures ◽  
A Chain ◽  
Poly Carbonate

New thermoplastic poly(carbonate-urethane) elastomersTwo series of novel thermoplastic poly(carbonate-urethane) elastomers, with different hard-segment content (30 - 60 wt %), were synthesized by melt polymerization from poly(hexane-1,6-diyl carbonate) diol of Mn= 2000 as a soft segment, 4,4'-diphenylmethane diisocyanate (MDI) or hexane-1,6-diyl diisocyanate (HDI) and 6,6'-[methylenebis(1,4-phenylenemethylenethio)]dihexan-1-ol as a chain extender. The structure and basic properties of the polymers were examined by Fourier transform infrared spectroscopy, X-ray diffraction analysis, atomic force microscopy, differential scanning calorimetry, thermogravimetric analysis, Shore hardness and tensile tests. The resulting TPUs were colorless polymers, showing almost amorphous structures. The MDI-based TPUs showed higher tensile strengths (up to 21.3 MPa vs. 15.8 MPa) and elongations at break (up to 550% vs. 425%), but poorer low-temperature properties than the HDI-based analogs.

Warpage Analysis of Different Number Cooling Channels for Dumbbell Plastic Part in Injection Moulding

2015 ◽  
Vol 761 ◽  
pp. 8-11 ◽  
Author(s):  
Mohd Amran ◽  
Siti Salmah ◽  
Raja Izamshah ◽  
Mohd Shahir ◽  
Mohd Amri ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Simulation Analysis ◽  
Cooling System ◽  
Cooling Channel ◽  
Mould Temperature ◽  
Plastic Part ◽  
Melt Temperature ◽  
Moulding Process ◽  
Cooling Channels ◽  
Injection Moulding Process

Warpage deflection is one of the common pitfalls in plastic injection moulding which is always affected the quality and accuracy of the plastic products. It occurs due to the influences of mould temperature during injection moulding process and it is related to the number of cooling system existed in the mould. Therefore, this paper studies the effect of cooling channels on warpage of dumbbell plastic part having different number of cooling channel using Moldflow software. Warpage analysis was run using four and eight cooling channels. Parameters involved in this study are injection time, packing time, melt temperature and mould temperature. The result of warpage from simulation analysis was projected on the graphic having different colour which is presented the actual value of warpage. It is found from warpage simulation result that the maximum warpage for four cooling channels is 1.283mm and the maximum warpage for eight cooling channels is 1.280mm. It shows that the increasing of the number of cooling channel from four to eight channels in the injection mould reduces the warpage deflection about 0.2%. Thus, the result shows that the number of cooling system in the mould plays an important role on the quality of plastic part during injection moulding process.

Cu(II) and Zn(II) Complexes with an N- and O-Donor Ligand: Structural Characterization, Jahn-Teller Effect and Fluorescence

2013 ◽  
Vol 68 (2) ◽  
pp. 147-154 ◽  
Author(s):  
Hai-Wei Kuai ◽  
Xiao-Chun Cheng ◽  
Xiao-Hong Zhu
Keyword(s):  
Structural Features ◽  
Chain Structure ◽  
Influential Factors ◽  
Teller Effect ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Donor Ligand ◽  
Jahn Teller ◽  
Jahn Teller Effect ◽  
A Chain

Cu(II) and Zn(II) salts react with 5-(1H-benzotriazol-1-ylmethyl)isophthalic acid (H2L) under hydrothermal conditions to yield two new complexes [Cu(L)(DMF)(H2O)] (1) and [Zn(L)] (2) [DMF=N,N-dimethylformamide], which have been characterized by single-crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. As a result, 1 shows a chain structure, further linked together by hydrogen bonding and π-π interactions to give rise to a 3D supramolecular framework. Complex 2 is a binodal (3,6)-connected 2D kgd network with (43)2(46.66.83) topology. The influential factors of synthetic strategies on coordination modes of the ligand and structures of the resulting complexes are embodied in the study. Significantly, 1 has structural features consistent with the Jahn-Teller effect. Furthermore, the fluorescence properties of 2 were preliminarily investigated.

scholarly journals Influence of Quenching Rate on the Structure, Morphology, and Hyperfine Parameters of Amorphous Ribbons

2016 ◽  
Vol 67 (5) ◽  
pp. 365-370
Author(s):  
Narges Amini ◽  
Július Dekan ◽  
Milan Pavúk ◽  
Safdar Habibi ◽  
Marcel Miglierini
Keyword(s):  
Melt Spinning ◽  
Structural Characteristics ◽  
Grazing Angle ◽  
Structural Features ◽  
Protective Atmosphere ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
Quenching Rate ◽  
Scanning Calorimetry ◽  
Dsc Measurements

AbstractIn this work, an amorphous alloy with the nominal composition of Fe78Si9B13was produced by a melt spinning method. Using different velocities of a quenching cooper wheel enabled us to study the influence of quenching rate upon the structural characteristics of the resulting ribbons. Structural features of the samples were checked by Mössbauer spectroscopy and X-ray diffraction. The latter performed in a grazing angle geometry enabled us to explore both sides of the as-quenched ribbons. The onset of crystallization was estimated by differential scanning calorimetry (DSC) measurements. Surface features of the ribbons were examined by Scanning Electron Microscopy (SEM). In order to observe structural relaxation phenomena the samples were annealed below the onset of crystallization at 450 °C for 1 hour in Ar protective atmosphere. Even though the annealed ribbons are still amorphous relevant changes were observed in their hyperfin parameters as derived from Mssbauer spectrometry.

A Review of the Effect of Process Parameters on the Performance of Plastic Injection Molding Process to Control the Warpage in Plastics

2015 ◽  
Vol 830-831 ◽  
pp. 116-119 ◽  
Author(s):  
Gurjeet Singh ◽  
Mohan Kumar Pradhan ◽  
Ajay Verma
Keyword(s):  
Process Parameters ◽  
Injection Moulding ◽  
Process Parameter ◽  
Coolant Temperature ◽  
Injection Molding Process ◽  
Melt Temperature ◽  
Influence Of Process Parameters ◽  
Moulding Process ◽  
Injection Moulding Process ◽  
Plastic Injection

Quality control is important aspect of manufacturing process. The quality of product in injection moulding is influenced by injection moulding process parameter. A study of the influence of process parameters on the injection moulding process is presented. Statistically based model approach were studied. In this the process parameter that affect the injection moulding process are like injection time, injection pressure, packing pressure, packing time, cooling time, coolant temperature mold temperature, melt temperature are studied and compared. This paper deals with design of experiment approach to fine out optimal parameter setting. The comparison shows effect of parameters on injection moulding process.Key words: Plastic injection moulding, Orthogonal array, Cycle time

scholarly journals Rheological characterization of polystyrene melts dissolved with supercritical nitrogen fluid during microcellular injection moulding

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shia-Chung Chen ◽  
Ming-Hsiu Chung ◽  
Yu-Wan Lin ◽  
Ping-Shun Hsu ◽  
Shyh- Shin Hwang ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Rheological Behaviour ◽  
Rheological Characterization ◽  
Melt Temperature ◽  
Moulding Process ◽  
Foaming Process ◽  
Lower Viscosity ◽  
Injection Moulding Process ◽  
Mould Cavity ◽  
Moulding Pressure

AbstractThere are several benefits of using the supercritical fluid microcellular injection moulding process. The part weight, melt temperature, viscosity, moulding pressure, shrink/warpage, and cooling/cycle time are all significantly reduced. The purpose of this study is to investigate the rheological behaviour of PS melt dissolved SCF of nitrogen during Microcellular Injection Moulding process applied with Gas Counter Pressure (GCP) technology. The application of gas into the mould cavity prior to the melt filling provides a counter force against the melt front advancement, restricting the foaming process during the melt filling stage. A slit cavity is designed to measure the pressure drop of polystyrene mixed with 0.4wt% supercritical nitrogen fluid under different mould temperatures (185°C, 195°C, and 205°C), injection speeds (5, 10, and 15 mm/s) as well as counter pressures (0, 150, 300 bars). It was found that melt viscosity is reduced by up to 30% when GCP is increased from 50 to 150 bar as compared to conventional injection moulding. The non-nucleation mixture melt obtained by using a GCP of 300 bar has 32~49% lower viscosity. In addition, the glass transition temperature, Tg, was found to be reduced from 96 °C to 50 °C when the applied GCP is 300 bar.

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