Effect Of Compatibilizer Research Articles

Kaolinite-based Janus nanosheets as effective compatibilizer of PLA/PBAT blend

To address the increasing global plastic pollution while the reducing oil supply, the biodegradable and bio-derived poly(lactic acid) (PLA) has been developed and considered to be the most promising substitute of petroleum-based plastics. However, the severe brittleness of PLA has become the obstacle of its broad application. Blending modification with poly(butylene-adipate-co-terephthalate) (PBAT) has been proved to be an potentially feasible strategy to toughen PLA, but conflicted by the poor compatibility between PLA and PBAT. To tackle the problem, a comb-type clay-based Janus nanosheet of poly(methyl methacrylate- kaolinite- poly(butylene-adipate-co-terephthalate) (PMMA-Kaol-PBAT) was prepared by selectively grafting PMMA and PBAT separately on either sides of kaolinite Janus nanosheets (JNS). PBAT was functionalized with quaternary amine via aminolysis before being cation-exchanged onto the siloxane tetrahedral surface (STS) side of kaolinite nanosheets, while PMMA chains were grafted onto the aluminoxyl octahedral surface (AOS) side after a beforehand surface modification with the silane coupling agent KH-570. Introduced in the PLA/PBAT blend system, the PMMA-Kaol-PBAT was found to enrich at the interface, enhancing the phase compatibility with the phase separation and aggregation inhibited during the film coating and annealing process.

Effect of polyacrylic acid‐polypropylene‐polyacrylic acid triblock copolymers with different acid content on mechanical properties of carbon fiber/polypropylene composites

AbstractThe use of polyacrylic acid‐polypropylene‐polyacrylic acid triblock copolymers (PAA‐iPP‐PAA, abbreviated as iPP‐PAA) with different acrylic acid contents (9, 19.5, 29 wt%) as compatibilizers for carbon fiber (CF)/polypropylene (PP) composites and their effect on the tensile properties of the composites were investigated. The addition of iPP‐PAA improved the tensile properties of the CF/PP composites. This enhancement in mechanical properties was considered to be due to the hydrogen bonding network between iPP‐PAAs, which improved the mechanical properties of the matrix resin itself, and to hydrogen bonding between carbon fiber surface and iPP‐PAAs, which improved the interfacial adhesion. A higher acrylic acid content of iPP‐PAA resulted in better interfacial properties; however, excessive acrylic acid content adversely affected the crystallinity and tensile properties of the composite, which suggests that there is an optimum acrylic acid content for the iPP‐PAA. The results indicated that iPP‐PAA is an effective compatibilizer in CF/PP composites, and the iPP‐PAA with the best performance had an acrylic acid content of 19.5%.Highlights PAA‐PP‐PAA copolymers used as compatibilizers for CF/PP composites. Acrylic acid content of PAA‐PP‐PAA varied as 9%, 19.5%, and 29%. Tensile properties of CF/PP composites enhanced by iPP‐PAA addition. Hydrogen bonding improved mechanical properties of matrix resin and CF‐resin adhesion. Optimum acrylic acid content for CF/PP composite was 19.5%.

Super Tough PA6/PP/ABS/SEBS Blends Compatibilized by a Combination of Multi-Phase Compatibilizers.

Development of multi-component blends to prepare high-performance polymer materials is still challenging, and is a key technology for mechanical recycling of waste plastics. However, a multi-phase compatibilizer is prerequisite to create high-performance multi-component blends. In this study, POE-g-(MAH-co-St) and SEBS-g-(MAH-co-St) compatibilizers are prepared via melt-grafting of maleic anhydride (MAH) and styrene (St) dual monomers to polyolefin elastomer (POE) and poly [styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS), respectively. Subsequently, these compatibilizers are utilized to compatibilize the PA6/PP/ABS/SEBS quaternary blends through melt-blending. When POE-g-(MAH-co-St) and SEBS-g-(MAH-co-St) are added, respectively, both can promote the distribution of the dispersed phases, significantly reducing the dispersed phase size. When adding 10 wt% POE-g-(MAH-co-St) and 10 wt% SEBS-g-(MAH-co-St) together, compared to the non-compatibilized blend, the fracture strength, fracture elongation, and impact strength surprisingly increased by 106%, 593%, and 823%, respectively. It can be attributed to the hierarchical interfacial interactions which facilitate gradual energy dissipation from weak to strong interfaces, resulting in the improvement of mechanical properties. The synergistic effect of the enhanced phase interfacial interactions and toughening effect of elastomer compatibilizer achieved simultaneous growth in strength and toughness.

Tough and biodegradable poly(lactic acid)/polybutylene adipate-co-terephthalate blends for screw-based 3D printing: Interfacial compatibilizing via reactive carbon nanotubes

Reactive nanoparticles were recently reported as novel and highly effective compatibilizers for biodegradable polymer blends. In this work, three kinds of reactive carbon nanotubes with low, medium, and high vinylsilane grafting ratios (VCNT-L, VCNT-M, and VCNT-H) were synthesized, and their compatibilizing efficiencies were studied. Poly(lactic acid)/polybutylene adipate-co-terephthalate (PLA/PBAT) blends for 3D printing were prepared by reactive blending PLA and PBAT with either of VCNT-L, VCNT-M, and VCNT-H in the presence of organic peroxide. Tough and biodegradable 3D printed samples were achieved by using PLA/PBAT blends reactively compatibilized by VCNT-M and VCNT-H. The impact strength of 3D printed blend samples containing VCNT-M and VCNT-H is 4.1 and 6.2 folds to that of 3D printed PLA samples, respectively. The high interfacial compatibilizing efficiency of both VCNT-M and VCNT-H for PLA/PBAT blend was evidenced by SEM and linear rheological examining results. However, the VCNT-L tended to induce large size PBAT phase domains, hence the poor interfacial adhesion. As a result, 3D printed PLA/PBAT blend samples containing VCNT-L exhibited low impact strength, closing to that of PLA samples. Apart from the remarkable compatibilizing effects, the VCNT-H was observed to significantly improve the interlayer adhesion of the 3D printed samples.

Bio-based epoxidized cardanol sorbate as an interface-localized compatibilizer for enhancing poly(lactic acid) (PLA) and poly(3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P34HB) blend

PLA is a bio-based polyester with limited barrier and flexible properties. Adding poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P34HB), a biodegradable polyester known for its outstanding barrier properties, was the strategy employed to boost PLA performance. However, the blend’s immiscibility necessitates compatibilizers to bolster interfacial adhesion and dispersion. This study designed a novel bio-based compatibilizer, epoxidized cardanol sorbate (ECD-SA), to improve the compatibility of the blend. The molecular design of ECD-SA has been optimized to minimize steric hindrance, thereby enhancing interfacial reactions more effectively. Two commercial compatibilizers, specifically ADR 4468 and NC-514, were selected for comparison. Theoretical model was employed to calculate dispersion preferences of three different compatibilizers in the blend. A systematic investigation was carried out to analyze the effects of compatibilizers on the structure and properties of PLA/P34HB blends. The findings suggest that ECD-SA functions as an interface-localized compatibilizer in PLA/P34HB blends, enhancing their compatibility and performance significantly. Specifically, the incorporation of 2 phr (parts per hundred resin) ECD-SA into the PLA/P34HB film resulted in a marked increase in tensile strength from 35.6 MPa and 23.5 MPa to 48.6 MPa and 36 MPa in the longitudinal and transverse directions, respectively, and an increase in elongation at break from 31.9 % and 9.2 % to 104.8 % and 48.3 %, respectively. This underscores its significant potential as a compatibilizer for PLA/P34HB, pointing towards extensive application possibilities in present-day packaging industries.

Synergistic effects of dual reactive compatibilizers for high-performance fully biodegradable polylactic acid/poly (butyleneadipate-co-terephthalate) composites

The PLA-g-(GMA-co-St) graft copolymer (PGS) was prepared using melt-free radical grafting technology, PGS and ESO were simultaneously employed as compatibilizers for the poly (lactic acid)/poly (butylene adipate-co-terephthalate) (PLA/PBAT) blends. The effects of the type and amount of compatibilizers on the properties of the blends were studied. The results reveal that the epoxy groups in PGS and ESO can interact with the terminal groups of PLA and PBAT. The incorporation of either PGS or ESO separately can improve the compatibility between PLA and PBAT to a considerable degree. However, the introduction of both compatibilizers into the PLA/PBAT blends results in a notable shift of the Tg of the two phases, reduces the size of PBAT particles, and makes their dispersion more uniform. This reveals that the dual reactive compatibilizers can achieve a synergistic effect, significantly reduced the interfacial tension between the two phases and facilitated inter-phase dispersion, ultimately forming a more uniform microstructure. Simultaneously, as the amount of ESO added to the blends gradually increase, the vicat softening temperature and complete decomposition temperature of the blends continue to increase, the notched impact strength and elongation at the break of the blends gradually increase and then decrease. When the ESO amount reaches 4 wt%, the performance of each property increases to 88.9 °C, 447.66 °C, 335.16 %, and 23,359.30 J/m2, respectively. At this point, the fracture surface of the blend samples is accompanied by a large-scale plastic deformation. In conclusion, this work represents the first attempt to accomplish synergistic effects via dual reactive compatibilizers. Under the best formulation and processing circumstances, the PLA/PBAT blends greatly increase their overall performance while maintaining biodegradability, hence broadening their application prospects in packaging, agriculture, and disposable tableware.

Physico-Thermal and Mechanical Characterization of Alfa Fiber/Polypropylene Composites: Effects of Fiber Treatment and MAPP Compatibilization

ABSTRACT This study investigates the enhancement of compatibility between natural reinforcement materials and polymer matrices, with a focus on Alfa fibers polypropylene (PP) composites. Composites Alfa fibers/PP are prepared using untreated and treated alfa fibers and with or without the addition of a MAPP compatibilizing agent. Firstly, Alfa fibers extracted from the plant are categorized into two groups: untreated and treated with a 3% (wt/v) alkaline solution followed by bleaching. This chemical treatment significantly increases the cellulose content and crystallinity index of the fibers, with improvements of 39.7% and 13.6%, respectively. Secondly, the study incorporates 5 wt% MAPP in the PP matrix as a compatibilizer. The composites produced with 30 wt% of alfa fibers are processed using a single screw extruder, followed by injection molding. Composites samples obtained are characterized using various methods. Thermal analysis reveals that the incorporation of chemically treated alfa fibers along with MAPP significantly accelerates the crystallization rate of the PP matrix, indicating the fibers’ role as effective nucleating agents. Mechanical testing shows marked improvements in the Young’s modulus and tensile strength of the composites obtained with treated alfa fibers reinforcing the MAPP-PP matrix, with increases of 1.67% and 4.61% over their untreated counterparts, respectively.

Biodegradable composites from poly(butylene adipate‐co‐terephthalate) with soybean protein isolate: Preparation, characterization, and performances

AbstractSoy protein isolate (SPI), a widely available and inexpensive natural polymer, can be used as a filler to reduce the cost of poly(butylene adipate‐co‐terephthalate) (PBAT) materials. To improve the compatibility between SPI and PBAT, a series of polycaprolactone‐based polyurethane prepolymers (PCLPUs) with different soft segment molecular weights were synthesized and used as compatibilizers to prepare SPI/PBAT composites. At the same time, the effect of PCLPU soft segment molecular weight on the properties of SPI/PBAT composites was studied. Structural, morphological, and property analyses were carried out on the composite materials; the results showed that PCLPU was an effective compatibilizer for SPI/PBAT composite materials. The –NCO group at its end forms a urethane bond with the hydroxyl group in SPI and PBAT. At the same time, the soft segment of PCLPU is physically crosslinked with PBAT to produce a dual physical and chemical effect. The lower the soft segment molecular weight of PCLPU added, the better the performance of the SPI/PBAT composite materials. This is observed because PCLPU with a lower soft segment molecular weight contains more –NCO functional groups, which can better achieve compatibilization between SPI and PBAT through chemical crosslinking. The addition of 5% PCLPU‐500 content to the SPI/PBAT composite material increased its tensile elongation, impact strength, and tensile strength by 867%, 264%, and 150%, respectively, compared with those of the SPI/PBAT composite material without a compatibilizer, achieving toughening and strengthening with good processability and biodegradability. This work provides a simple, effective solution for preparing high‐performance, green, and low‐cost biodegradable composite materials.Highlights PBAT composites were prepared using soy protein isolate (SPI) as filler. Different types of PCLPU exist as a reactive compatibilizer for PBAT and SPI. Polycaprolactone‐based polyurethane prepolymer significantly improves the interfacial compatibility of PBAT composites. SPI/PBAT film has good degradability and is a rich source of nitrogen.

Nanodiamond Nano-Reinforcements in Thermoplastic (Polyamide, Polyimide, Polystyrene) Nanocomposites—Essential Characteristics and Technicalities

Nanodiamonds are unique spherical carbon nano-entities having the advantages of very high surface area and high optical, thermal, wear and strength characteristics. Like other carbonaceous nanoparticles (like fullerene, graphene or carbon nanotube), nanodiamond nano-reinforcements have been investigated for the significant types of polymeric matrices (such as thermosets, thermoplastics, rubbers) nanocomposites. Consequently, this overview was planned to systematically describe the current scientific status of the nanodiamonds reinforced thermoplastic nanomaterials. In this regard, polyamide/nanodiamonds, polyimide/nanodiamonds and polystyrene/nanodiamonds nanocomposites have been fabricated using the facile solution, in-situ and melt mixing techniques. We suggest that including nanodiamonds in polyamides and polyimides increased their engineering characteristics, like mechanical properties and thermal stability, of the resulting nanocomposites due to a distinct interface formation and their compatibilization effects toward these matrices. Correspondingly, including nanodiamonds in polystyrene has been observed to increase the intrinsically low strength/toughness features of this polymer. Predominantly, nano-reinforcement and miscibility effects of the nanodiamonds with the polystyrene and their mutual matrix-nanofiller synergies were responsible to improve the overall microstructural and physical properties of the resulting nanocomposites. As per our analysis, the research reports so far on the important categories of the nanodiamonds reinforced thermoplastic matrix nanocomposites have shown important technical applications in the fields of high-tech coatings, membranes and energy devices.

Interfacial compatibilization of fully biodegradable polylactic acid/polybutylene adipate terephthalate blends for improved mechanical and physical performance

Environmental problems, such as plastic pollution and global warming, are motivating researchers worldwide to seek sustainable biodegradable polymers that would replace the nonbiodegradable ones. Polylactic acid (PLA) has emerged as one of the most promising alternatives due to its superior mechanical and thermal qualities compared to other types of biopolymers. However, PLA has some inherent deficiencies such as its brittleness and rigidity, which limit its further use. This study investigates the toughening effect of different amounts of polybutylene adipate terephthalate (PBAT) on PLA, and the compatibilization effect of ADR, a chain extender, on the PLA/PBAT blends. The results indicate that PBAT can significantly enhance the flexibility and toughness of PLA. PLA and PBAT can react with ADR to form PLA-g-PBAT copolymers thereby increasing the compatibility of these two polymers. The tensile strength, elongation at break and impact strength of the PLA/PBAT/ADR blends are all increased due to the increased compatibility. The chain extension reaction can promote the formation of a better crystalline structure in the PLA/PBAT blends, which leads to the increase of the Tm of PLA. Besides, the hydrophilicity of PLA can be adjusted by blending with PBAT, and the hydrophilicity of the blends with blend ratios of 75:25, 50:50 and 25:75 can also be enhanced after the addition of ADR.

A Dynamic Mechanical Analysis on the Compatibilization Effect of Two Different Polymer Waste-Based Compatibilizers in the Fifty/Fifty Polypropylene/Polyamide 6 Blend.

This study aims to examine the 50/50 polypropylene/polyamide 6 (iPP/PA6) system molded under confined flow conditions, both in its original state and after being modified by two different interfacial agents. This study provides two main insights. Firstly, it focuses on a polymer blend close to phase inversion. Secondly, it investigates the impact of using two different types of interfacial agents (derived from polymer waste) to enhance the compatibility between iPP and PA6. Dynamic Mechanical Analysis (DMA) has been employed to achieve these objectives. It is important to note that the investigation of the 50/50 iPP/PA6 system is a crucial focus predicted in previous studies, where a series of mechanical properties were evaluated using Box-Wilson design of experiments (DOEs) over the whole compositional range on the iPP/PA6 binary system. Thus, two interfacial modifiers, namely succinic anhydride (SA)-grafted atactic polypropylene with terminal, side, and bridge SA grafts (aPP-SASA) and succinyl-fluoresceine (SF) with bridge succinic anhydride grafting atactic polypropylene (aPP-SFSA), were employed. The authors obtained and characterized these agents. The quantity of these agents used in the blend was identified as a critical coordinate in prior studies conducted by the authors. The processing method used, compression molding under confined conditions, was chosen to minimize any orientation effect on the emerging morphology. All characterization procedures were performed on samples processed by contour machining to retain the blend morphologies as they emerged from the processing stage. Results from WAXS and SAXS synchrotron tests concluded there were no changes in the crystal morphology of the iPP or the PA6 in the blends nor any co-crystallization process throughout the compositional range. These findings, and the long period fits on the PP crystalline phase for the fifty/fifty blends we are discussing, will support the present DMA study. Finally, the efficiency of these interfacial modifiers has been concluded, even in this unfavorable scenario.

Preparation of Poly(Styrene-co-Acrylonitrile)-Grafted Attapulgite via Simultaneous Reverse and Normal Initiation Atom Transfer Radical Polymerization (SR&NI ATRP) and Its Effect on Polycarbonate/Acrylonitrile-Butadiene-Styrene Terpolymer Ternary Composites

To further improve the comprehensive properties of polycarbonate/acrylonitrile–butadiene–styrene terpolymer blends (PC/ABS), in this work, styrene–acrylonitrile copolymer [P(St-co-An)] was grafted on the surface of attapulgite particles (ATP) by simultaneous reverse and normal initiation ATRP (SR&NI ATRP) to yield ATP@P(St-co-An) hybrid particles. Then a series of PC/ABS/ATP@P(St-co-An) composites were prepared via the melt blending method. The effects of ATP@P(St-co-An) content on the morphological, mechanical, thermal and rheological properties of the composites were investigated in detail. The core-shell ATP@P(St-co-An) hybrid particles with the polymer layer thickness of 20-40 nm were synthesized successfully according to the results of X-ray photoelectron spectrometer (XPS), Fourier transform infrared spectrometer (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The improvement in mechanical properties, reduced glass transition temperature (T g) difference between PC and ABS and micromorphology changes of the composites proved the compatibilization, strengthening, and toughening effect of the ATP@P(St-co-An). Compared with the PC/ABS blend, with strength and toughness of 50.8 MPa and 56.3 kJ/m2, when the ATP@P(St-co-An) content was 4 wt%, a reasonable balance (85.8 MPa and 86.2 kJ/m2) between strength and toughness was achieved with substantially enhanced thermal stability. Moreover, the composite showed more remarkable non-Newtonian behavior, and its processability was also improved. We believe this work provides an effective approach to optimize the compatibility and comprehensive properties of PC/ABS blends.

A Promising Recycling Strategy via Processing Polypropylene/Recycled Poly(ethylene terephthalate): Reactive Extrusion Using Dual Compatibilizers.

Enhancing interfacial adhesion in polypropylene (PP)/recycled polyethylene terephthalate (rPET) blends is crucial for the effective mechanical recycling of these commercial plastic wastes. This study investigates the reactive extrusion of PP/rPET blends using a dual compatibilizer system comprising maleic anhydride grafted polypropylene (PP-g-MA) and various glycidyl methacrylate (GMA)-based compatibilizers. The effects of backbone structure and reactive group on the morphological, mechanical, and thermal characteristics were systematically studied. This study sheds light on the effective compatibilization mechanisms using characterization methods such as Fourier Transform Infrared Spectroscopy (FTIR) and morphological analyses (SEM). The results indicate that GMA-based compatibilizers play a bridging role between rPET and PP-g-MA, resulting in improved compatibility between the blend components. A combination of 3 phr PP-g-MA and 3 phr ethylene-methyl acrylate glycidyl methacrylate terpolymer (EMA-GMA) significantly improves interfacial adhesion, leading to synergistic enhancements of mechanical performance of the blend, up to 217% and 116% increases in elongation at break and impact strength, respectively, compared to the uncompatibilized sample. Moreover, a significant improvement in onset temperature for degradation is observed for the dual compatibilized sample, with 40 °C and 33 °C increases in onset temperature relative to the uncompatibilized and the single compatibilized samples. These findings underscore the immense potential of tailored multi-component compatibilizer systems for upgrading recycled plastic waste materials.

Investigation of thermodynamically induced nanoparticle localization in Poly(vinylidene fluoride)/Poly(lactic acid) blends with surface-grafted carbon nanotubes

Physically anchoring multi-walled carbon nanotubes (MWCNT) onto the polymer blend interface has been extensively investigated, however, the tunable localization of polymer grafted MWCNT in immiscible polymer blends is seldom reported. Herein, poly(methyl methacrylate) (PMMA) grafted MWCNT (PMMA-g-MWCNT) were nondestructively prepared via the surface-initiated atom transfer radical polymerization. The compatibilization effects of PMMA-g-MWCNT on morphology and mechanical properties of blend composites are investigated. The results demonstrate that the fillers are distributed at the blend interface due to the high affinity between PMMA and PVDF. The interaction between PMMA and PLA changes the crystallinity of blends. Moreover, the surface modification of MWCNT enhances the interaction of filler and matrix, and the elongation at break is as high as 52 % for composites with 10 % PMMA-g-MWCNT. The fracture surface of specimen after tensile tests exhibits an obvious ductile transition with filler contents. This work systematically discussed the relationship between the PMMA-g-MWCNT distribution and the mechanical strength of composites, which provided a solid experimental foundation on the toughening mechanism of PMMA-g-MWCNT used as a compatibilizer for PVDF/PLA blends.

Amide wax-assisted interfacial compatibilization of maleic anhydride-grafted polyethylene for high-performance wood-plastic composites

ABSTRACT The interfacial compatibility between wood fibers and plastics is one of the key problems in the preparation of high-performance wood-plastic composites (WPCs). However, the current compatibilization strategy primarily relies on a single compatibilizer, but the resulting effect is less than ideal. In this study, the combination of maleic anhydride-grafted polyethylene (MAPE) and amide wax (AW) was adopted for the synergistic compatibilization of WPCs. This approach enabled the high mobility of AW to fully penetrate the surfaces and voids of wood fibers, facilitating the interfacial migration of MAPE and resulting in strong compatibilization effects. The dual compatibilization mechanism was revealed based on the results of polarized light microscope (PLM), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). As a consequence, the WPCs compatibilized by MAPE and AW compounds possessed better thermal stability, as well as slightly higher dynamic modulus and complex viscosity. The tensile strength and flexural strength of the WPCs reached to 55 and 45 MPa, increased by approximately 26% compared to the WPCs compatibilized by single MAPE. The dual compatibilization strategy can effectively solve poor interfacial adhesion of WPCs, enabling the preparation of high-performance and environmental-friendly WPCs, and also be readily extended to other composites.

Effect of Compatibilizers on the Physico-mechanical Properties of a Poly(Lactic Acid)/ Poly(Butylene Adipate-co-terephthalate) Matrix with Rice Straw Micro-particle Fillers

Effect of Compatibilizers on the Physico-mechanical Properties of a Poly(Lactic Acid)/ Poly(Butylene Adipate-co-terephthalate) Matrix with Rice Straw Micro-particle Fillers

Nanoindentation Response of Structural Self-Healing Epoxy Resin: A Hybrid Experimental-Simulation Approach.

In recent years, self-healing polymers have emerged as a topic of considerable interest owing to their capability to partially restore material properties and thereby extend the product's lifespan. The main purpose of this study is to investigate the nanoindentation response in terms of hardness, reduced modulus, contact depth, and coefficient of friction of a self-healing resin developed for use in aeronautical and aerospace contexts. To achieve this, the bifunctional epoxy precursor underwent tailored functionalization to improve its toughness, facilitating effective compatibilization with a rubber phase dispersed within the host epoxy resin. This approach aimed to highlight the significant impact of the quantity and distribution of rubber domains within the resin on enhancing its mechanical properties. The main results are that pure resin (EP sample) exhibits a higher hardness (about 36.7% more) and reduced modulus (about 7% more), consequently leading to a lower contact depth and coefficient of friction (11.4% less) compared to other formulations that, conversely, are well-suited for preserving damage from mechanical stresses due to their capabilities in absorbing mechanical energy. Furthermore, finite element method (FEM) simulations of the nanoindentation process were conducted. The numerical results were meticulously compared with experimental data, demonstrating good agreement. The simulation study confirms that the EP sample with higher hardness and reduced modulus shows less penetration depth under the same applied load with respect to the other analyzed samples. Values of 877 nm (close to the experimental result of 876.1 nm) and 1010 nm (close to the experimental result of 1008.8 nm) were calculated for EP and the toughened self-healing sample (EP-R-160-T), respectively. The numerical results of the hardness provide a value of 0.42 GPa and 0.32 GPa for EP and EP-R-160-T, respectively, which match the experimental data of 0.41 GPa and 0.30 GPa. This validation of the FEM model underscores its efficacy in predicting the mechanical behavior of nanocomposite materials under nanoindentation. The proposed investigation aims to contribute knowledge and optimization tips about self-healing resins.

Preparation and properties of poly (butylene adipate‐co‐terephthalate) composites with high bamboo flour content

AbstractThis study focused on the preparation of bamboo flour/Poly (butylene adipate‐co‐terephthalate) (PBAT) composites with high bamboo flour content and high mechanical strength using polyurethane prepolymer as chemical–physical compatibilizer via in‐situ reaction. Additionally, this work explored the effects of different bamboo flour contents and different types of polyurethane prepolymers on the mechanical properties, morphology, thermodynamics, water absorption, and surface wettability of the bamboo flour/PBAT composites. The results showed that PBA‐based polyurethane prepolymer (PBAPU) was an effective compatibilizer, promoting the interfacial adhesion between bamboo flour and PBAT. The strength at break, elongation at break, and impact strength of composites with 50% bamboo flour content reached 19.56 MPa, 25.53%, and 12.8 KJ/m2. With the increase of bamboo flour content, the strength of composites was still higher. The addition of PBAPU enhanced the thermal stability, mechanical properties, water resistance, and hydroscopicity of the bamboo flour/PBAT composites. Furthermore, the compatibilization of PBA‐based polyurethane prepolymer on composites was better than that of PCL‐based polyurethane prepolymer. Overall, we provided an effective strategy for preparing renewable, green, and practical high‐bamboo flour composites.Highlights This work successfully prepared bamboo flour/PBAT composites with high bamboo content using an in‐situ melt blending reaction. A new interface structure of physical PBA‐PBA interaction between the PBAPU layer and PBAT matrix improved the compatibilization of the composites. PBAPU as a compatibilizer effectively improved the interface compatibility, thermal stability, and water resistance of Bamboo flour/PBAT blends. Bamboo flour/PBAT composites with high bamboo flour content have excellent mechanical properties.

Foamability of all‐green polylactide/rice straw pulp biocomposites through continuous extrusion process: Effects of pulping and reactive compatibilization

AbstractIn the present work, the processability of poly(lactic acid) (PLA) in the extrusion foaming process was improved by using rice straw (RS) as an agricultural waste. In order to extrude a sustainable lightweight foam, the soda‐pulping and bleaching modification were performed on the RS particles, which resulted in the attainment of purified micron‐sized cellulosic fibre with higher aspect ratio. The addition of these fibres, with larger interfacial area between filler and matrix, to the PLA melt enhanced the foam void fraction and cell density more than one order of magnitude. The use of a reactive compatibilizer in the biocomposite showed further beneficial effects on the PLA foamability. The used reactive compatibilizer, with the ability of simultaneous reactions with the end groups of PLA macromolecules and hydroxyl groups of the lignocellulosic pulp, in the biocomposite noticeably improved the viscoelastic properties of melt and lengthened the macromolecule relaxation times. As a result, the biocomposite melt with higher melt strength was obtained, which kept the melt integrity during the bubble growth stage, hindered the cell coalescence, and retained a larger volume of gas inside the melt. Contrary to these influences, the compatibilization activity of this additive weakened the heterogeneous nucleation role of the cellulosic fibres. However, by choosing proper pulp loading, the extrusion of a lightweight biodegradable PLA‐based biocomposite foam can be feasible, which can be used in interior construction applications.

Effect of Different Compatibilizers on the Properties of Green Low-Density Polyethylene Composites Reinforced with Bambusa Vulgaris Bamboo Fibers.

Low-density green polyethylene (LDGPE) composites reinforced with 5 wt% of bamboo fiber and 3 wt% of a compatibilizing agent (polyethylene grafted with maleic anhydride and tannin) were processed through extrusion and injection molding. Bamboo fiber, Bambusa Vulgaris, was characterized using Fourier-transform infrared spectroscopy (FTIR). The molded specimens were analyzed for their thermal, mechanical, and morphological properties. The estimated concentration was chosen to provide the best mechanical strength to the material studied. FTIR analysis of the fibers revealed the presence of groups characteristic of bamboo fiber and tannin. Differential scanning calorimetry revealed that both compatibilizing agents increased the matrix's degree of crystallinity. However, scanning electron microscopy (SEM) showed that, despite the presence of compatibilizing agents, there was no significant improvement in adhesion between the bamboo fibers and LDGPE.