The Preparation and Properties of Nanocomposite from Bio-Based Polyurethane and Graphene Oxide for Gas Separation

Petroleum depletion and climate change have inspired research on bio-based polymers and CO2 capture. Tung-oil-based polyols were applied to partially replace polyether-type polyols from petroleum for sustainable polyurethane. Tung-oil-based polyurethane (TBPU), was prepared via a two-step polycondensation, that is, bulk prepolymerization and chain extension reaction. The graphene oxide (GO) was prepared via Hummer’s method. Then, TBPU was composited with the GO at different ratios to form a TBPU/GO hybrid film. The GO/TBPU films were characterized by fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermal gravimetric analysis (TGA) and scanning electron microscope (SEM), followed by the measurement of mechanical properties and gas permeability. The results showed that the addition of tung-oil-based polyols enhanced the glass transition temperature and thermal stability of TBPU. The mechanical properties of the hybrid film were significantly improved, and the tensile strength and elongation at break were twice as high as those of the bulk TBPU film. When the GO content was higher than 2.0%, a brittle fracture appeared in the cross section of hybrid film. The increase of GO content in hybrid films improved the selectivity of CO2/N2 separation. When the GO content was higher than 0.35%, the resulting GO agglomeration constrained the gas separation and permeation properties.

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Effect of Graphene Oxide-Boron Nitride-Based Dual Fillers on Mechanical Behavior of Epoxy/Glass Fiber Composites

Journal of Nanomaterials ◽

10.1155/2021/5047641 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

V. Kavimani ◽

P. M. Gopal ◽

B. Stalin ◽

Alagar Karthick ◽

S. Arivukkarasan ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Graphene Oxide ◽

Boron Nitride ◽

Glass Fiber ◽

Matrix Composite ◽

Matrix Material ◽

Gravimetric Analysis ◽

Fiber Matrix ◽

Thermal Stability Of

Graphene and its derivatives have excellent properties such as high surface area, thermal, and mechanical strength, and this fact made the researchers promote them as the possible filler material for fiber-matrix composite. The current research deals with validation on the effect of graphene oxide boron nitride filler over mechanical and thermal stability of epoxy glass fiber polymer matrix composite. The objective of this experimental investigation is to develop glass fiber reinforced polymer composites with hybrid filler addition. The matrix material selected is epoxy resin, whereas the glass fiber is selected as reinforcement, while boron nitride and graphene oxide are chosen as fillers. Compression moulding methodology is followed to develop the composites with the constant percentage of fiber loading, graphene oxide filler, and varying boron nitride content from 0 to 3 wt.% at an equal interval of 1 wt.%. The developed composite is analyzed for mechanical properties, and the fractured surface is analyzed through the scanning electron microscope. The addition of hybrid fillers enhances the fiber-matrix bonding strength and improves the thermal and mechanical properties up to a specific limit. Thermal gravimetric analysis was conducted to understand the thermal behavior of composite. The results revealed that the addition of filler improved the thermal stability of the composites.

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Effect of Organic Modifier Types on the Physical–Mechanical Properties and Overall Migration of Post-Consumer Polypropylene/Clay Nanocomposites for Food Packaging

Polymers ◽

10.3390/polym13091502 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1502

Author(s):

Eliezer Velásquez ◽

Sebastián Espinoza ◽

Ximena Valenzuela ◽

Luan Garrido ◽

María José Galotto ◽

...

Keyword(s):

Mechanical Properties ◽

Food Packaging ◽

Clay Nanocomposites ◽

Organic Modifier ◽

Thermal And Mechanical Properties ◽

Chemical Safety ◽

Elongation At Break ◽

Fatty Food ◽

Recycled Plastics ◽

Thermal Stability Of

The deterioration of the physical–mechanical properties and loss of the chemical safety of plastics after consumption are topics of concern for food packaging applications. Incorporating nanoclays is an alternative to improve the performance of recycled plastics. However, properties and overall migration from polymer/clay nanocomposites to food require to be evaluated case-by-case. This work aimed to investigate the effect of organic modifier types of clays on the structural, thermal and mechanical properties and the overall migration of nanocomposites based on 50/50 virgin and recycled post-consumer polypropylene blend (VPP/RPP) and organoclays for food packaging applications. The clay with the most hydrophobic organic modifier caused higher thermal stability of the nanocomposites and greater intercalation of polypropylene between clay mineral layers but increased the overall migration to a fatty food simulant. This migration value was higher from the 50/50 VPP/RPP film than from VPP. Nonetheless, clays reduced the migration and even more when the clay had greater hydrophilicity because of lower interactions between the nanocomposite and the fatty simulant. Conversely, nanocomposites and VPP/RPP control films exhibited low migration values in the acid and non-acid food simulants. Regarding tensile parameters, elongation at break values of PP film significantly increased with RPP addition, but the incorporation of organoclays reduced its ductility to values closer to the VPP.

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Hyperbranched polyamide modified graphene oxide-reinforced polyurethane nanocomposites with enhanced mechanical properties

RSC Advances ◽

10.1039/d1ra00654a ◽

2021 ◽

Vol 11 (24) ◽

pp. 14484-14494

Author(s):

Yahao Liu ◽

Jian Zheng ◽

Xiao Zhang ◽

Yongqiang Du ◽

Guibo Yu ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

High Performance ◽

Cross Linking ◽

Elongation At Break ◽

Modified Graphene Oxide ◽

High Performance Composite ◽

Modified Graphene ◽

Polyurethane Nanocomposites ◽

Hyperbranched Polyamide

We successfully modified graphene oxide with amino-terminated hyperbranched polyamide (HGO), and obtained a high-performance composite with enhanced strength and elongation at break via cross-linking hydroxyl-terminated polybutadiene chains with HGO.

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The effect of large area graphene oxide (LAGO) nanosheets on the mechanical properties of polyvinyl alcohol

Journal of Polymer Engineering ◽

10.1515/polyeng-2015-0271 ◽

2016 ◽

Vol 36 (4) ◽

pp. 399-405 ◽

Cited By ~ 1

Author(s):

Khalid Nawaz ◽

Muhammad Ayub ◽

Noaman Ul-Haq ◽

M.B. Khan ◽

Muhammad Bilal Khan Niazi ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Graphene Oxide ◽

Polyvinyl Alcohol ◽

Molecular Level ◽

Large Area ◽

Graphene Oxides ◽

Elongation At Break ◽

Graphene Oxide Sheets ◽

Excellent Improvement

Abstract Large area graphene oxide sheets were synthesized, dispersed in water and used as nanofiller for mechanical improvement in terms of Young’s modulus and ultimate tensile strength (UTS) of polyvinyl alcohol (PVA) at low loading. The molecular level dispersion and interfacial interactions between the graphene oxides and polymeric matrix PVA were the real challenges. An excellent improvement in mechanical properties at 0.35 wt% loading was observed. Modulus improved from 1.58 GPa to 2.72 GPa (~71% improvement), UTS improved from 120 MPa to 197 MPa (~65% improvement), and in spite of these improvements, interestingly, there was no fall in elongation at break at this loading.

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Sericin cocoon bio-compatibilizer for reactive blending of thermoplastic cassava starch

Scientific Reports ◽

10.1038/s41598-021-99417-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Thanongsak Chaiyaso ◽

Pornchai Rachtanapun ◽

Nanthicha Thajai ◽

Krittameth Kiattipornpithak ◽

Pensak Jantrawut ◽

...

Keyword(s):

Mechanical Properties ◽

Maleic Anhydride ◽

Crystal Size ◽

Thermoplastic Starch ◽

Cassava Starch ◽

Chain Extension ◽

Amino Groups ◽

Reactive Blending ◽

Elongation At Break ◽

Small Crystal Size

AbstractCassava starch was blended with glycerol to prepare thermoplastic starch (TPS). Thermoplastic starch was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented polyethylene grafted maleic anhydride particles (2 μm) dispersed in the thermoplastic starch matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of polyethylene grafted maleic anhydride (121 °C) decreased to 111 °C because of the small crystal size of the polyethylene grafted maleic anhydride phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of polyethylene grafted maleic anhydride. This reaction reduced the interfacial tension between thermoplastic starch and polyethylene grafted maleic anhydride, which improved the compatibility, mechanical properties, and morphology of the blend.

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Crystallization, Structure and Significantly Improved Mechanical Properties of PLA/PPC Blends Compatibilized with PLA-PPC Copolymers Produced by Reactions Initiated with TBT or TDI

Polymers ◽

10.3390/polym13193245 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3245

Author(s):

Lixin Song ◽

Yongchao Li ◽

Xiangyu Meng ◽

Ting Wang ◽

Ying Shi ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Strength ◽

Average Molecular Weight ◽

Toluene Diisocyanate ◽

Chain Extension ◽

Poly Lactic Acid ◽

Cooling Process ◽

Material Degradation ◽

Elongation At Break ◽

Poly Propylene

Poly (lactic acid) (PLA)-Poly (propylene carbonate) (PPC) block copolymer compatibilizers are produced in incompatible 70wt%PLA/PPC blend by initiating transesterification with addition of 1% of tetra butyl titanate (TBT) or by chain extension with addition of 2% of 2,4-toluene diisocyanate (TDI). The above blends can have much better mechanical properties than the blend without TBT and TDI. The elongation at break is dramatically larger (114% with 2% of TDI and 60% with 1% of TBT) than the blend without TDI and TBT, with a slightly lower mechanical strength. A small fraction of the copolymer is likely formed in the PLA/PPC blend with addition of TBT, and a significant amount of the copolymer can be made with addition of TDI. The copolymer produced with TDI has PPC as a major content (~70 wt%) and forms a miscible interphase with its own Tg. The crystallinity of the blend with TDI is significantly lower than the blend without TDI, as the PLA blocks of the copolymer in the interphase is hardly to crystallize. The average molecular weight increases significantly with addition of TDI, likely compensating the lower mechanical strength due to lower crystallinity. Material degradation can occur with addition of TBT, but it is very limited with 1% of TBT. However, compared with the blends without TBT, the PLA crystallinity of the blend with 1%TBT increases sharply during the cooling process, which likely compensates the loss of mechanical strength due to the slightly material degradation. The added TDI does not have any significant impact on PLA lamellar packing, but the addition of TBT can make PLA lamellar packing much less ordered, presumably resulted from much smaller PPC domains formed in the blend due to better compatibility.

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Preparation and Characteristic of PC/PLA/TPU Blends by Reactive Extrusion

Advances in Materials Science and Engineering ◽

10.1155/2015/393582 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Yueyun Zhou ◽

Lifa Luo ◽

Wenyong Liu ◽

Guangsheng Zeng ◽

Yi Chen

Keyword(s):

Mechanical Properties ◽

Fracture Behavior ◽

Reactive Extrusion ◽

Uniform Structure ◽

Intrinsic Properties ◽

Elongation At Break ◽

The Poor ◽

Properties Of Materials ◽

The Impact ◽

Thermal Stability Of

To overcome the poor toughness of PC/PLA blends due to the intrinsic properties of materials and poor compatibility, thermoplastic urethane (TPU) was added to PC/PLA blends as a toughener; meantime, catalyst di-n-butyltin oxide (DBTO) was also added for catalyzing transesterification of components in order to modify the compatibility of blends. The mechanical, thermal, and rheological properties of blends were investigated systematically. The results showed that the addition of TPU improves the toughness of PC/PLA blends significantly, with the increase of TPU, the elongation at break increases considerably, and the impact strength increases firstly and then falls, while the tensile strength decreases significantly and the blends exhibit a typical plastic fracture behavior. Meantime, TPU is conducive to the crystallinity of PLA in blends which is inhibited seriously by PC and damages the thermal stability of blends slightly. Moreover, the increased TPU makes the apparent viscosity of blends melt decrease due to the well melt fluidity of TPU; the melt is closer to the pseudoplasticity melt. Remarkably, the transesterification between the components improves the compatibility of blends significantly, and more uniform structure results in a higher crystallinity and better mechanical properties.

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Sericin cocoon bio-compatibilizer for reactive blending of thermoplastic cassava starch

10.21203/rs.3.rs-701614/v1 ◽

2021 ◽

Author(s):

Thanongsak Chaiyaso ◽

Pornchai Rachtanapun ◽

Nanthicha Thajai ◽

Krittameth kiattipronpithak ◽

Pensak Jantrawut ◽

...

Keyword(s):

Mechanical Properties ◽

Maleic Anhydride ◽

Crystal Size ◽

Thermoplastic Starch ◽

Cassava Starch ◽

Chain Extension ◽

Amino Groups ◽

Reactive Blending ◽

Elongation At Break ◽

Small Crystal Size

Abstract Cassava starch was blended with glycerol to prepare thermoplastic starch (TPS). TPS was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented PEMAH particles (2 µm) dispersed in the TPS matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of PEMAH (121°C) decreased to 111°C because of the small crystal size of the PEMAH phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy (FTIR) confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of PEMAH. This reaction reduced the interfacial tension between TPS and PEMAH, which improved the compatibility, mechanical properties, and morphology of the blend.

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Solid-State Compounding for Recycling of Sawdust Waste into Green Packaging Composites

Processes ◽

10.3390/pr8111386 ◽

2020 ◽

Vol 8 (11) ◽

pp. 1386

Author(s):

Rula M. Allaf ◽

Mohammad Futian

Keyword(s):

Solid State ◽

Thermo Gravimetric Analysis ◽

Contact Angles ◽

Raw Material ◽

Potential Candidate ◽

Gravimetric Analysis ◽

Water Contact ◽

Elongation At Break ◽

Green Packaging ◽

Thermal Stability Of

The present study explores solid-state cryomilling for the compounding of green composites. Herein, wood plastic composites (WPCs) composed of sawdust (SD) and poly(ε-caprolactone) (PCL) with various compositions were prepared. Two compounding techniques, namely, extrusion and cryomilling, were utilized to prepare WPC raw material pellets and powders, respectively, for comparison purposes. Flat pressing was further utilized to prepare WPC films for testing. Morphological, structural, thermal, mechanical, and surface wettability properties were investigated. Results indicate the advantages of cryomilling in producing WPCs. Scanning electron microscopy (SEM) along with optical micrographs revealed well ground SD particles and uniform distribution in the PCL matrix. Tensile strength and elongation at break of the composites declined with increasing SD content, however, the modulus of elasticity significantly increased. Water contact angles averaged less than 90°, implying partial wetting. Visual observations and thermo-gravimetric analysis (TGA) indicated thermal stability of composites during processing. In conclusion, PCL/SD WPC is a potential candidate to replace conventional plastics for packaging applications. This would also provide a much better utilization of the currently undervalued wood waste resources.

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Effects of Imidization Temperature on the Structure and Properties of Electrospun Polyimide Nanofibers

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501400900404 ◽

2014 ◽

Vol 9 (4) ◽

pp. 155892501400900 ◽

Cited By ~ 1

Author(s):

Xuejia Li ◽

Xin Wang ◽

Qingqing Wang ◽

Qufu Wei

Keyword(s):

Thermal Stability ◽

Chemical Structure ◽

Testing Machine ◽

Gravimetric Analysis ◽

Elongation At Break ◽

Universal Testing ◽

Thermal Imidization ◽

Ft Ir ◽

Nanofiber Membranes ◽

Thermal Stability Of

A two-step process for preparing polyimide nanofiber was used in this work, and the nanofibers of precursor polyamic acid (PAA) were prepared by electrospinning. The polyimide nanofibers were obtained through thermal imidization at different thermal imidization temperatures. The influences of different imidization temperatures on morphology, chemical structure, thermal stability, and mechanical properties of the polyimide nanofibers were investigated by Fourier Transform Infrared Spectroscope (FT-IR), Scanning Electronic Microscopy (SEM), thermal gravimetric analysis (TGA) and Electromechanical Universal Testing Machine. The experimental results show that the imidization of PAA nanofibers was not complete under 290°C but complete under 350°C. With the rise of imidization temperature from 290 °C to 350°C, the polyimide nanofibers became thinner, and the thermal stability of polyimide nanofibers was also improved. The breaking strength and elongation at break of the nanofiber membranes increased at higher imidization temperature.

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