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

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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Toughening Modification of Polylactic Acid by Thermoplastic Silicone Polyurethane Elastomer

Polymers ◽

10.3390/polym13121953 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1953

Author(s):

Mingtao Sun ◽

Shuang Huang ◽

Muhuo Yu ◽

Keqing Han

Keyword(s):

Mechanical Properties ◽

Polylactic Acid ◽

Mechanical Analysis ◽

Melt Blending ◽

Pseudoplastic Fluid ◽

Obvious Effect ◽

Elongation At Break ◽

Thermodynamic Compatibility ◽

The Poor ◽

The Impact

The melt blending of polylactic acid (PLA) and thermoplastic silicone polyurethane (TPSiU) elastomer was performed to toughen PLA. The molecular structure, crystallization, thermal properties, compatibility, mechanical properties and rheological properties of the PLA/TPSiU blends of different mass ratios (100/0, 95/5, 90/10, 85/15 and 80/20) were investigated. The results showed that TPSiU was effectively blended into PLA, but no chemical reaction occurred. The addition of TPSiU had no obvious effect on the glass transition temperature and melting temperature of PLA, but slightly reduced the crystallinity of PLA. The morphology and dynamic mechanical analysis results demonstrated the poor thermodynamic compatibility between PLA and TPSiU. Rheological behavior studies showed that PLA/TPSiU melt was typically pseudoplastic fluid. As the content of TPSiU increased, the apparent viscosity of PLA/TPSiU blends showed a trend of rising first and then falling. The addition of TPSiU had a significant effect on the mechanical properties of PLA/TPSiU blends. When the content of TPSiU was 15 wt%, the elongation at break of the PLA/TPSiU blend reached 22.3% (5.0 times that of pure PLA), and the impact strength reached 19.3 kJ/m2 (4.9 times that of pure PLA), suggesting the favorable toughening effect.

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Preparation and Property Research of PC/PLA Composites Modified By ABS Blending

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.66-68.1902 ◽

2011 ◽

Vol 66-68 ◽

pp. 1902-1907 ◽

Cited By ~ 5

Author(s):

Yi Chen ◽

Guang Sheng Zeng ◽

Ping Jiang ◽

Xiang Gang Li ◽

Yu Gang Huang

Keyword(s):

Mechanical Properties ◽

Impact Resistance ◽

Compound System ◽

Melt Blending ◽

Crystallization Ability ◽

Great Performance ◽

Optimum Proportion ◽

Properties Of Materials ◽

The Impact ◽

Thermal Stability Of

PC/PLA composite material introduces the degradability of PLA to PC with great performance, but their compatibility and impact resistance are poor. Aiming at this deficiency, ABS is used to modify PC/PLA. This paper established the ternary compound system of PC/PLA/ABS by melt blending and studied the impact of adding ABS and compatibilizer ABS-g-MAH on the composite’s morphology, thermal properties, rheology and mechanical properties. The results showed that: ABS bettered the brittle fracture of PC/PLA and improved the impact strength of composite with the optimum proportion of 30% of PC/PLA mass. In addition, ABS-g-MAH effectively improved the compatibility of the composites as well as mechanical properties of materials. With the increase of ABS, the crystallization ability of PLA in the composite improved and the thermal stability of the system deteriorated slightly, the melt shear viscosity of composite also decreased.

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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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Improving Rheological and Mechanical Properties of Various Virgin and Recycled Polypropylenes by Blending with Long-Chain Branched Polypropylene

Polymers ◽

10.3390/polym13071137 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1137

Author(s):

Sascha Stanic ◽

Thomas Koch ◽

Klaus Schmid ◽

Simone Knaus ◽

Vasiliki-Maria Archodoulaki

Keyword(s):

Mechanical Properties ◽

Molecular Weight ◽

Tensile Test ◽

Reactive Extrusion ◽

Original Material ◽

Melt Flow Rate ◽

Single Screw Extruder ◽

Pp Blends ◽

The Impact ◽

Long Chain

Blends of two long-chain branched polypropylenes (LCB-PP) and five linear polypropylenes (L-PP) were prepared in a single screw extruder at 240 °C. The two LCB-PPs were self-created via reactive extrusion at 180 °C by using dimyristyl peroxydicarbonate (PODIC C126) and dilauroyl peroxide (LP) as peroxides. For blending two virgin and three recycled PPs like coffee caps, yoghurt cups and buckets with different melt flow rate (MFR) values were used. The influence of using blends was assessed by investigating the rheological (dynamic and extensional rheology) and mechanical properties (tensile test and impact tensile test). The dynamic rheology indicated that the molecular weight as well as the molecular weight distribution could be increased or broadened. Also the melt strength behavior could be improved by using the two peroxide modified LCB-PP blends on the basis of PODIC C126 or PEROXAN LP (dilauroyl peroxide). In addition, the mechanical properties were consistently enhanced or at least kept constant compared to the original material. In particular, the impact tensile strength but also the elongation at break could be increased considerably. This study showed that the blending of LCB-PP can increase the investigated properties and represents a promising option, especially when using recycled PP, which demonstrates a real “up-cycling” process.

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Effects of Solidification Cooling Rate on the Microstructure and Mechanical Properties of a Cast Al-Si-Cu-Mg-Ni Piston Alloy

Materials ◽

10.3390/ma11071230 ◽

2018 ◽

Vol 11 (7) ◽

pp. 1230 ◽

Cited By ~ 9

Author(s):

Lusha Tian ◽

Yongchun Guo ◽

Jianping Li ◽

Feng Xia ◽

Minxian Liang ◽

...

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Eutectic Silicon ◽

Model Alloy ◽

Chinese Script ◽

Uniform Structure ◽

Elongation At Break ◽

Piston Alloy ◽

Δ Phase ◽

Al3ni Phase

The effects of cooling rate 0.15, 1.5, 15, 150, and 1.5 × 105 °C/s on the microstructures and mechanical properties of Al-13Si-4Cu-1Mg-2Ni cast piston alloy were investigated. The results show that with an increase of solidification cooling rate, the secondary dendrite arm spacing (SDAS) of this model alloy can be calculated using the formula D = 47.126v − 1/3. The phases formed during the solidification with lower cooling rates primarily consist of eutectic silicon, M-Mg2Si phase, γ-Al7Cu4Ni phase, δ-Al3CuNi phase, ε-Al3Ni phase, and Q-Al5Cu2Mg8Si6 phase. With the increase in the solidification cooling rate from 0.15 to 15 °C/s, the hardness increased from 80.9 to 125.7 HB, the room temperature tensile strength enhanced from 189.3 to 282.5 MPa, and the elongation at break increased from 1.6% to 2.8%. The ε -Al3Ni phase disappears in the alloy and the Q phase emerges. The δ phase and the γ phase change from large-sized meshes and clusters to smaller meshes and Chinese script patterns. Further increase in the cooling rate leads to the micro hardness increasing gradually from 131.2 to 195.6 HV and the alloy solidifying into a uniform structure and forming nanocrystals.

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Mechanical Properties of PVC/ABS Composite Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.217-218.1170 ◽

2011 ◽

Vol 217-218 ◽

pp. 1170-1173

Author(s):

Wei Wei Qiao ◽

Hui Wang ◽

Yan Hua Zhao ◽

Yi Xia Han

Keyword(s):

Mechanical Properties ◽

Composite Material ◽

Testing Machine ◽

Impact Testing ◽

Elongation At Break ◽

Poly Vinyl Chloride ◽

Maximum Value ◽

Material Testing Machine ◽

The Impact ◽

Butadiene Styrene

We investigate the mechanical properties of Poly Vinyl Chloride (PVC)/ acrylnitrile-butadiene-styrene copolymer (ABS) composite material with an impact testing machine，a material testing machine and other accessory devices. The result shows that the mechanical properties of PVC/ABS composite are a function of composition, the addition of ABS improved the mechanical properties of PVC/ ABS composite，the impact strength and elongation at break rise significantly with increasing ABS content in PVC/ABS composite and appears maximum value，While the tensile strength and modulus almost decrease monotonously with increasing ABS content in PVC/ABS composite.

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Structure and mechanical properties of GR/UHMWPE nanocomposite ropes

E3S Web of Conferences ◽

10.1051/e3sconf/201913101127 ◽

2019 ◽

Vol 131 ◽

pp. 01127

Author(s):

Wen Wen Yu ◽

Jian Gao Shi ◽

Yong Li Liu ◽

Lei Wang

Keyword(s):

Mechanical Properties ◽

Melt Spinning ◽

Mechanical Test ◽

Reactive Extrusion ◽

Breaking Load ◽

Hot Water ◽

Test Results ◽

Screw Extruder ◽

Elongation At Break ◽

Ultra High Molecular Weight

Ultra-high molecular weight polyethylene (UHMWPE) and graphene (GR) was melt compounded by reactive extrusion. Nanocomposite monofilaments were prepared by melt spinning through a co-rotating screw extruder and drawing at hot water. GR/UHMWPE nanocomposite ropes were twisted using nanocomposite monofilaments. A structure and mechanical properties of the GR/UHMWPE nanocomposite monofilaments and its ropes had been characterized by scanning electron microscopy (SEM), and mechanical test. Results showed that the monofilaments surface of monofilaments became rougher with introducing of GR nanosheets, which could be related to stacking of GR. The breaking load of GR/UHMWPE nanocomposite ropes was remarkably improved upon nanofiller addition, with the decrease of the elongation at break.

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Rigid Polyurethane Foams Reinforced with POSS-Impregnated Sugar Beet Pulp Filler

Materials ◽

10.3390/ma13235493 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5493

Author(s):

Anna Strąkowska ◽

Sylwia Członka ◽

Agnė Kairytė

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Sugar Beet ◽

Sugar Beet Pulp ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Limiting Oxygen Index ◽

Composite Foams ◽

Beet Pulp ◽

The Impact ◽

Thermal Stability Of

Rigid polyurethane (PUR) foams were reinforced with sugar beet pulp (BP) impregnated with Aminopropylisobutyl-polyhedral oligomeric silsesquioxanes (APIB-POSS). BP filler was incorporated into PUR at different percentages—1, 2, and 5 wt.%. The impact of BP filler on morphology features, mechanical performances, and thermal stability of PUR was examined. The results revealed that the greatest improvement in physico-mechanical properties was observed at lower concentrations (1 and 2 wt.%) of BP filler. For example, when compared with neat PUR foams, the addition of 2 wt.% of BP resulted in the formation of PUR composite foams with increased compressive strength (~12%), greater flexural strength (~12%), and better impact strength (~6%). The results of thermogravimetric analysis (TGA) revealed that, due to the good thermal stability of POSS-impregnated BP filler, the reinforced PUR composite foams were characterized by better thermal stability—for example, by increasing the content of BP filler up to 5 wt.%, the mass residue measured at 600 °C increased from 29.0 to 31.9%. Moreover, the addition of each amount of filler resulted in the improvement of fire resistance of PUR composite foams, which was determined by measuring the value of heat peak release (pHRR), total heat release (THR), total smoke release (TSR), limiting oxygen index (LOI), and the amount of carbon monoxide (CO) and carbon dioxide (CO2) released during the combustion. The greatest improvement was observed for PUR composite foams with 2 wt.% of BP filler. The results presented in the current study indicate that the addition of a proper amount of POSS-impregnated BP filler may be an effective approach to the synthesis of PUR composites with improved physico-mechanical properties. Due to the outstanding properties of PUR composite foams reinforced with POSS-impregnated BP, such developed materials may be successfully used as thermal insulation materials in the building and construction industry.

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Effect of Multiwalled Carbon Nanotubes (MWNT) on the Properties of High Impact Polystyrene (HIPS)

Journal of Nanomaterials ◽

10.1155/2018/8305721 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Juan Li

Keyword(s):

Thermal Stability ◽

Flame Retardancy ◽

High Impact ◽

Melt Blending ◽

Flow Properties ◽

Multiwalled Carbon ◽

Elongation At Break ◽

Morphological Behavior ◽

The Impact ◽

Thermal Stability Of

The composites of HIPS/MWNT were prepared by melt blending. The effects of the content of MWNT on the flow, mechanical, and flame retardancy properties of the composites were investigated. The morphologies of fracture surfaces were characterized through scanning electron microscopy (SEM). And the thermal stability of the composites was studied by thermogravimetric analysis. The results show that the flow properties, the impact strength, the elongation at break, and the flame retardancy are improved with the proper addition of MWNT. The morphological behavior indicates the fracture surface of HIPS/MWNT is more roughness than that of HIPS. The addition of MWNT has little influence on the thermal stability of HIPS.

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Novel robust ion-specific responsive photonic hydrogel elastomers

Journal of Materials Chemistry C ◽

10.1039/c9tc02513h ◽

2019 ◽

Vol 7 (29) ◽

pp. 8946-8953 ◽

Cited By ~ 3

Author(s):

Wenzhao Liu ◽

Li Li ◽

Suni Liu ◽

Bing Liu ◽

Zhaoyang Wu ◽

...

Keyword(s):

Mechanical Properties ◽

Structural Color ◽

Practical Applications ◽

The Poor ◽

Mechanical Properties Of Materials ◽

Properties Of Materials ◽

External Stimuli

Embedded photonic hydrogels that can change structural color as a result of external stimuli have shown great potential for various applications, but their practical applications have been limited due to the poor mechanical properties of materials.

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