Notched Impact Strength Research Articles

Improving the performance of polylactic acid/polypropylene/cotton stalk fiber composites with epoxidized soybean oil as a high efficiency plasticizer.

Polylactic acid (PLA) can serve as a biodegradable alternative to traditional petroleum-based plastics, but its poor impact resistance and high production costs limit its applications. In this study, different contents of epoxidized epoxy soybean oil (ESO) were added as plasticizer to melt blend with polylactic acid (PLA), polypropylene (PP) and cotton stalk fiber (CSF), examining its impact on the mechanical properties, thermal stability, microstructure, and crystallization behavior of the blends. The results indicated that ESO reacted with PLA and CSF to form branched polymers and microgels. With increasing ESO content, the blends exhibited increased initial thermal decomposition temperature, impact strength, and elongation at break, while stiffness, maximum decomposition rate, and crystallinity decreased. When the mass ratio of CSF to ESO was 2:1, the notch impact strength and elongation at break of PLA/PP/CSF/ESO blends were 1.63 times and 1.98 times higher than those of PLA/PP/CSF blends, respectively. Moreover, a reduction in surface grooves of CSF and formation of a gel layer were observed. Importantly, this study opens an effective new pathway for the utilization of waste natural fibers and the widespread application of biodegradable composite materials, contributing to environmental protection, resource conservation, and cost reduction.

Developing high-performance and sustainable polylactic acid/recycled polyolefin blends: Tuning the degree of functional group reaction and performance optimization.

In the current development of the plastics industry, the use of biodegradable and recycled plastics not only effectively reduces the volume of landfills and incineration but also significantly decreases environmental damage. However, the extensive application of biodegradable polylactic acid (PLA) is limited by its poor toughness and thermal properties. The study introduced recycled linear low-density polyethylene (R-LLDPE) and ethylene-octene copolymer (POE) to modify PLA, primarily based on their excellent toughness and thermal resistance. Furthermore, being a recycled material, R-LLDPE is economically advantageous and conforms to the ecological requirements of resource recycling. Therefore study introduced glycidyl methacrylate (GMA) and styrene (St) to synthesize the graft copolymer (R-LLDPE/POE)-g-(GMA-co-St) (RPGS). The RPGS serves as a modifier for PLA resin. The effects of different GMA amounts in RPGS on the properties and microstructure of PLA/RPGS blends were examined. The results illustrate that GMA was successfully grafted onto the molecular chains of R-LLDPE/POE (RP), with St acting as a "bridge" to enhance further the grafting efficiency of GMA on RP macromolecular chains. After introducing RPGS into the PLA matrix, the epoxy groups of GMA reacted with the terminal hydroxyl groups of PLA, significantly decreasing the particle size of the dispersed phase and closely integrating with the PLA matrix, hence greatly improving the compatibility between PLA and RP. With the increase of GMA amount, the optical, thermal, and hydrophobic properties of the blends were increased, while the flexibility first increased and then decreased. When the GMA amounts were 5 wt% in RPGS, the Gd and Ge of GMA reached optimal values of 2.55 % and 51 %, the blend exhibited the optimum overall properties: haze decreased to 28.3 %, light transmittance increased to 92.5 %, thermal decomposition temperature increased to 368.12 °C, and the Vicat softening temperature increased to 78.2 °C. While maintaining the tensile strength at 54.3 MPa, the notched impact strength and elongation at break increased to 10,182.4 J/m2 and 231.7 %, respectively, with the matrix exhibiting significant shear yielding. The research presents an eco-friendly and efficient method for producing high-performance PLA-based materials, effectively addressing the shortcomings of PLA in toughness and thermal resistance. The modified materials had excellent mechanical and thermal capabilities while offering financial and environmental benefits. The development of this material is anticipated to enhance the industrial utilization of biodegradable and recycled plastics, offering essential support for attaining sustainable manufacturing and a circular economy.

A novel bio-based ferric flame retardant effectively improving the flame retardancy and mechanical properties of polylactic acid

PTDF is prepared by a convenient ionic reaction of phytic acid, terephthalic dihydrazide and iron salts in water. It is a new type of high efficiency flame retardant. PTDF has high phosphorus and nitrogen content and good thermal stability, which can effectively improve the flame retardancy of PLA. PTFE is an anti-drip agent and is often used to improve the flame retardancy of PLA together with flame retardants. The addition of 4 wt% PTDF and 0.1 wt% PTFE made PLA reach V-0 flame retardant grade from non-flame retardant, and the oxygen index increased from 19.5 % to 24.5 %. With the increase of PTDF content, the performance of PLA improved significantly. The peak heat release rate (PHRR) and THR of PLA/6PTDF composites decrease by 27.4 % and 16.2 %, respectively, and the flame retardant index FRI increase by 232 %, showing excellent flame retardant efficiency. 6 wt% PTDF can increase the crystallinity of PLA by 25.9 %, tensile strength, maximum force required for impact fracture and notch impact strength by 12 %, 37 % and 129 %, respectively, and effectively improve the mechanical properties and toughness of the composite. The bio-based flame-retardant PLA/PTDF composites reported in this paper can be applied to office equipment.

Flame retardancy, thermal, and mechanical properties of flame retardant PA6/SGF and PPS/PA6/SGF composites

AbstractFlame retardant polyamide 6/short glass fiber (FR PA6/SGF) and polyphenylene sulfide/PA6/SGF (FR PPS/PA6/SGF) composites were prepared by melt extrusion blending using aluminum diethylphosphinate (ADPP) as flame retardant. The thermogravimetric analysis (TGA) indicated that the flame retardant composites showed good thermal degradation with increasing ADPP loading. Flame retardancy mechanisms were studied by analyzing the residue chars. ADPP provided better flame inhibition, promoted formation of carbonaceous char, and improved thermal stability of PA6/SGF. Meanwhile, due to the self‐extinguishing performance of PPS, the flame retardancy of PPS/PA6/SGF was greatly affected by only 3.0 wt% of ADPP. With increasing ADPP content, both storage and loss moduli of FR PA6/SGF and FR PPS/PA6/SGF were increased accompanied with a slight increase of tan δ peak as compared to PA6/SGF and PPS/PA6/SGF, respectively. Besides, notched impact strengths of FR PA6/SGF‐10.0 and FR PPS/PA6/SGF‐10.0 increased by 69% and 5%, while tensile strengths decreased by approximately 5% and 32%, as compared to PA6/SGF and PPS/PA6/SGF, respectively. It demonstrates that ADPP and PPS components are efficient inorganic–organic hybrid flame retardant system. This provides a novel and innovative method for preparing halogen‐free flame retardant reinforced polyamide composites.

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.

Effect of the synergistic interaction of zinc adipate, hydrotalcite and ethylene propylene rubber on the performances of polypropylene

Polypropylene (PP) is widely used in a range of areas due to its excellent physical and chemical properties, but its low-temperature brittleness and low-impact resistance largely limits its application. Hence, this study investigated the changes in mechanical and thermal properties of isotactic polypropylene (iPP) modified by the addition of the β-nucleating agent zinc adipate (ZnAA), the inorganic rigid particle hydrotalcite (HT), and the rubber elastomer bipropylene rubber (EPR). The structure and properties of modified PP were investigated by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), electronic universal material testing machine, and simple-beam impact testing machine. At last, the non-isothermal crystallization kinetics of iPP was investigated by the Caze method. It was found that with the addition of EPR reached 30 wt%, the notched impact strength of iPP was 34.74 kJ/m2, which was 542.43 % higher than that of pure iPP, and more than twice as high as that of ZnAA and HT modification, and the relative crystallinity ( K β) value of the β-crystalline form reached 79.66 % when 10 wt% EPR was added to the iPP. The addition of ZnAA, HT and EPR could significantly increase the crystallisation peak temperature ( T c), shorten the half-crystallisation time ( t 1/2) and increase the crystallisation activation energy ( ΔE) of iPP.

Influence of Twin Screw Extrusion Conditions on MWCNT Length and Dispersion and Resulting Electrical and Mechanical Properties of Polycarbonate Composites

The processing conditions were varied during the production of polycarbonate-based composites with the multiwalled carbon nanotubes (MWCNTs) Baytubes® C150 P (Bayer MaterialScience AG, Leverkusen, Germany), by melt mixing with an extruder on a laboratory scale. These included the screw design, rotation speed, throughput, feeding position and MWCNT content. Particular attention was paid to the shortening of the MWCNT length as a function of the conditions mentioned. It was found that there is a correlation between the applied specific mechanical energy (SME) during the melt mixing process and MWCNT dispersion, which was quantified by the agglomerate area ratio of the non-dispersed nanotubes based on optical microscopic analysis. The higher the SME value, the lower this ratio, which indicates better dispersion. Above an SME value of about 0.4 kWh/kg, no further improvement in dispersion was achieved. The MWCNT length, as measured by the quantitative analysis of TEM images of the MWCNTs dissolved from the composites, decreased with the SME value down to values of 44% of the original MWCNT length. At a constant loading of 3 wt.%, the tensile strength and tensile modulus were almost independent of the SME, while the elongation at break and notched impact strength showed an increasing trend. The variation in the feeding position showed that feeding the MWCNTs into a side feeder led to slightly better electrical and mechanical properties for both types of MWCNTs studied (Baytubes® C150 P and Nanocyl™ NC7000 (Nanocyl S.A., Sambreville, Belgium)). However, feeding into the hopper led to better CNT dispersion with Baytubes® C150 P, while this was the case with Nanocyl™ NC7000 when feeding into the side feeder. The screw profile had an influence on the dispersion, the MWCNT length and the electrical resistance, but only to a small extent. Distributive screws led to a greater shortening of the MWCNT length than dispersive screws. By varying the MWCNT content, it was shown that a greater MWCNT shortening occurred at higher loadings. Two-stage masterbatch dilution leads to stronger shortening than composite production with direct MWCNT incorporation.

Preparation of super toughened flame-retardant polylactic acid with an in situ hyperbranched structure by reactive blending with a phosphorus-containing copolyester and hexamethylene glycidyl cyclotriphosphazene

Achieving both super toughness and flame retardancy in polylactic acid (PLA) materials hinges on resolving the interface compatibility issues between flame retardants, toughening agents, and PLA, as well as overcoming potential antagonisms between these components. Here, we present an approach employing hyperbranched structures to simultaneously enhance the toughness and flame retardancy of PLA materials. Our strategy involved the reactive blending of PLA with a quaternary bio-based phosphorus-containing copolyester (PPE) featuring side hydroxyl groups and hexamethylene glycidyl cyclotriphosphazene (HGCP). The multi-epoxy groups of HGCP reacted with the hydroxyl and carboxyl groups present in PPE and PLA, resulting in the formation of hyperbranched PLA-PPE copolymers. The hyperbranched copolymers provided great interfacial compatibilization and low viscosity, synergistically promoting the melt-dripping flame-retardant mechanism facilitated by PPE, aiding in the rapid removal of heat and combustible material from the pyrolysis zone. Consequently, the PLA/PPE/HGCP blends exhibited super toughness, achieving a maximum notched impact strength of 70.2 kJ/m2. Additionally, the blends demonstrated a 27 % LOI and can pass the UL-94 V-0 rating. Moreover, all the blends are biodegradable in a Proteinase K solution. This research underscores the efficacy of utilizing hyperbranched structures as a promising strategy for the development of PLA materials with simultaneous enhancement of processability, toughness, and flame retardancy.

An innovative functional compatibility strategy for poly (lactic acid) and polypropylene carbonate blends to achieve superior toughness, degradability, and optical properties

This study, for the first time, unveils the potential of dibutyl itaconate (DBI) in enhancing the compatibility between PLA (poly (lactic acid)) and PPC (polypropylene carbonate), systematically investigating the effects of DBI amount on the thermal, optical, rheological, mechanical, and degradation properties and microstructure of the PLA/PPC/DBI blends. The results showed that DBI could chemically react with PLA and PPC, forming a PLA-co-DBI-co-PPC copolymer structure, thereby improving the compatibility between PLA and PPC. When the DBI amount reached 8 wt%, only one Tg was observed in the blend system, and no distinct phase interface was visible in the fracture surface of the blend specimens. This indicated that at this DBI amount, the PLA and PPC had transitioned from a partially compatible system to a fully compatible system. With the increase in DBI amount in the system, the elongation at break and notched impact strength of the blends initially increased and then decreased, while the storage modulus, loss modulus, and complex viscosity showed a gradual downward trend. When the DBI amount increased to 10 wt%, the flexibility of the blends reached its peak, with the values rising to 494.7 % and 8494.1 J/m2, respectively, representing 13.7 times and 2.5 times those of the neat PLA/PPC blends. At this point, the impact specimens exhibited significant plastic flow in the direction of force, showing distinct ductile fracture characteristics. Meanwhile, the degradation performance of the PLA/PPC blends increased with the addition of DBI. The introduction of DBI effectively facilitated the penetration of water molecules into the PLA/PPC molecular chains, enhancing the hydrolysis of ester bonds, leading to a maximum mass loss rate of 84.1 %, which was significantly higher than the 20.3 % of the neat PLA/PPC blends. In addition, the addition of DBI significantly reduced the haze of the blends while maintaining high light transmittance, demonstrating excellent optical properties (light transmittance remained above 92.4 %, and haze decreased from 37.1 % to 11.1 %). In conclusion, this study provides a new approach for the development of high-performance PLA-based biodegradable composites. The resulting blends exhibit excellent toughness, degradation performance, and optical properties, significantly enhancing their application potential in fields such as disposable products, packaging, agriculture, and 3D printing materials.

Highly enhanced toughness and thermal oxygen aging resistance of PA 6 via novel designed macromolecular antioxidants

Polyamide 6 (PA6) is widely utilized, yet it confronts challenges such as susceptibility to thermal oxidative aging and high sensitivity to notch impact during usage. In addressing these issues, two novel toughening macromolecular antioxidants, 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid 2-acrylamidoethyl ester styrene copolymer (PAS) and 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid 2-acrylamidoethyl-N-phenylmaleimide copolymer (PAN), were synthesized via free radical copolymerization. Upon incorporation into PA6, their effects on PA6 performance were investigated. Relative to pure PA6, PA6/PAN and PA6/PAS exhibited significant improvements in fracture elongation, with increases of 136.91 % and 313.83 % respectively, along with notch impact strength enhancements of 18.55 % and 24.89 % respectively. This enhancement can be attributed to PAN and PAS reducing the hydrogen bond density between PA6 molecular chains. Subsequent long-term accelerated thermal aging tests conducted at 150 °C, as well as performance testing of samples before and after aging, revealed that the aging of PA6/PAN and PA6/PAS could be delayed by 4–12 days. The exceptional anti-thermal oxidative aging ability and toughening effect of these two macromolecular antioxidants in PA6 showcase promising prospects for its expanded applications.

Study on epoxy bonding properties of thermoplastic polyurethane/polyphenylene sulfide composites reinforced by surface-modified basalt fiber

In this study, in order to improve the epoxy bonding properties of thermoplastic polyurethane (TPU)/polyphenylene sulfide (PPS) composites, the surface of the basalt fiber (BF) was modified by using 3-Glycidyloxypropyltrimethoxysilane (KH-560) as a modifier to obtain K-BF. The K-BF/TPU/PPS composites were prepared by injection molding. The surface properties of the composites were evaluated by using various tests and characterizations, including contact angle measurements, laser confocal microscopy and X-ray photoelectron spectroscopy. Furthermore, the epoxy bonding properties and mechanical properties of the composites were assessed through single-lap-joint tensile shear strength tests and notched impact tests. The results showed that KH-560 was successfully grafted onto BF surface and surface-modified K-BF was prepared. After the addition of K-BF, the contact angle of the K-BF/TPU/PPS composites was reduced, the wettability was enhanced, the surface roughness was elevated, and the content of polar groups was increased, which could effectively improve the epoxy bonding properties of TPU/PPS composites. Notably, when the K-BF was added at 35 wt%, the composite exhibited the best overall properties. It demonstrated a single-lap-joint tensile shear strength was 5.76 MPa, which was 151.53% higher than that of TPU/PPS and 326.67% higher than that of pure PPS. Moreover, the notched impact strength was 5.99 kJ·m−2, which was 155.98% higher than that of TPU/PPS and 248.26% higher than that of pure PPS.

Excellent flame-retardant polycarbonate composites with improved notched impact toughness via introducing imine-functionalized polysiloxane

Polycarbonate (PC) is known to suffer from damage over time, particularly in low-temperature settings besides its inherent flammability, where it can develop notches and lose its impact toughness. To address these issues, we synthesized schiff-based polysiloxane containing the benzene substituted with methoxy (referred to as PSOMe-X, X being the number of methoxy substitution on the benzene ring). Interestingly, by merely increasing the number of methoxy substitutions in PSOMe-X, the PC/PSOMe-X composites demonstrated significantly improved comprehensive performance. The PC/PSOMe-3 composite successfully passed the UL-94 (vertical burning test for Flammability of Plastic Materials for Parts in Devices and Appliances developed by Underwriters Laboratories) V-0 rating, and the limiting oxygen index (LOI) was increased to 29.9 %. This improvement was accompanied by a notable reduction in the peak heat release rate (PHRR) by 64 % and total smoke generation (TSP) by 18 %. Meanwhile the notched impact strength of the PC/PSOMe-3 composite was improved by 190 % at room temperature and 72 % at −25 °C. The mechanism for improved flame retardancy and impact tougheness for PC/PSOMe-X composites were unveiled.

Mechanism of improving the mechanical and barrier properties of poly(lactide)/poly(butylene adipate‐co‐terephthalate) blends

AbstractPoly(lactide)/poly(butylene adipate‐co‐terephthalate) (PLA/PBAT) blends containing different amounts of polyethylene wax (PEW) were fabricated via melt‐blending, and the effects of PEW on the interfacial morphological evolution and properties of the PLA/PBAT blends were investigated. Scanning electron microscopy (SEM) micrographs show that the compatibility between PLA and PBAT is obviously improved by addition of low contents of PEW. Differential scanning calorimeter (DSC) results indicate that PEW can simultaneously enhance the crystallization ability of PLA and PBAT. Rheological behavior of the blends indicates that PEW has a significant plasticizing effect and can promote the mobility of polymer chains in the blends. More importantly, it is revealed that PEW can effectively improve the mechanical and barrier properties of the blends. Even with a PEW content of only 1 wt%, the elongation at break and notched impact strength of the blend reach 344.1% and 12.55 kJ/m2, respectively, which are 54% and 140% higher than the blend without PEW. Meanwhile, the water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) of the films containing 1 wt% PEW are decreased from 87.34 to 67.40 g m−2·24 h−1 and from 118.26 to 80.94 cm3 m−2·24 h−1, respectively, which are 22.8% and 31.5% lower than those of the PLA/PBAT film.

Poly(Butylene Succinate) Copolyesters Modified with Linear‐Chain Diols toward Adjustable Thermal, Mechanical, and Biodegradable Properties

AbstractThe production and application of poly(butylene succinate) (PBS) still face challenges such as high production costs, insufficient toughness, and slow biodegradation. This study utilizes the ring‐opening condensation polymerization method to prepare PBS copolyesters using succinic anhydride (SAA) and 1,4‐butanediol (BDO) as raw materials, with 20 moL% different lengths of linear‐chain diols as third monomers (carbon numbers are 3, 5, 6, 8, 9,10, and 12). Both PBS and its copolyesters exhibit high weight average molecular weights (18.8 × 104–26.1 × 104 g moL−1), much higher than those obtained through the traditional conventional direct esterification method. Incorporating the third monomer reduces the glass transition temperature (Tg), crystallinity, and melting point (Tm) of the copolyesters. As the chain length of the third monomer increases, the copolyesters show improved toughness, with the elongation at break and notch impact strength of poly(butylene succinate‐ran‐dodecylene succinate) (P(BS‐ran‐DoS)) increasing from 374.1% and 5.6 KJ m−2 of PBS to 723.2% and 64.8 KJ m−2, respectively. The degradation rate of the copolyesters modified with short‐chain diols increases significantly, and as the chain length of the third monomer increases, the degradation rate of the copolyesters slows down. Therefore, the selection of the third monomer can be used to adjust the properties of the polymer.

Waste derived polysulphide coating on fly ash as fillers in plastic composite

Modifying fly ash (FA) for filler application can facilitate a cleaner, high volume and high value-application of FA. One of the major hurdles of utilizing unencapsulated FA as fillers is due to its hydrophilicity and tendency to leach out metals. The current study aims to develop a surface-modified FA (SuMo FA) as a suitable filler by coating it with a cross-linked polysulfide polymer from waste sulphur and oil derivatives. A Class F FA was coated with an in-house developed polysulfide polymer and was followed by a series of physicochemical analysis and 24-h batch leaching tests. This SuMo FA was compounded within PP and PE matrix and its thermo-mechanical properties were evaluated. The novel SuMo FA was ideal for filler application as it exhibited suitable spherical shape and size, hydrophobicity (contact angle ≅120°), and reduced leaching potential. Major contaminants (B, Cr, Pb, and Sr) in leachate of SuMo FA decreased by more than one order. Compounding the SuMo FA in polypropylene (PP) and polyethylene (PE) at 20 % (by weight) increased the onset temperature as compared to virgin polymers as well as filler-based polymers (with uncoated FA and CaCO3). Similarly, the SuMo FA filled polymers exhibited the best overall mechanical properties (under flexural and tensile loading) as well as notch impact strength. The Shore D hardness implies that SuMo FA filled polymers were almost identical to the conventionally used CaCO3 filled polymers. The leachate concentration of final PP composites with FA and SuMo FA fillers were lower than the regulatory limit for B, Ba, Cr and Sr. The developed filler material from the SuMo FA can potentially reduce dependence on relatively costly CaCO3 fillers in polymer production thus adhering to United Nation sustainable development goals (6 and 12).

Preparation and properties of toughened/flame‐retardant PA6/glass‐fiber composites reinforced by linear polyphosphazene elastomers

AbstractIn this study, the challenges of brittleness and flammability in Polyamide 6/glass fiber (PA6/GF) composites, which are crucial for heat‐resistant and stress‐bearing structural parts, are addressed. Polyphosphazene (PZ) elastomers, known for their exceptional flame‐retardant properties, are introduced to enhance the robustness and safety of these composites. Specifically, poly(diaryloxy)phosphazene (PDAP) and poly(difluoroalkoxy)phosphazene (PDFP) are utilized, both contributing to the improved toughness and flame resistance of the PA6/GF composites. Experimental results show that PDAP mainly played the role of solid‐phase flame retardant, while PDFP mainly acted the role of gas‐phase flame retardant. For PA/PZs composites without adding GF, PDFP plays a more efficient flame retardant effect than PDAP. By introducing 15 Vol% of PDFP, the limiting oxygen index (LOI) of the composite reached 26.1%, while the notched impact strength increased by 297%. For PA/PZs/GF composites, PDAP plays a better flame retardant role than PDFP. Under the action of 30 vol% GF and 15 vol% PDAP, the LOI of PA6/PDAP/GF composite reached 26.8%, and the notch impact strength improved to 18.7 kJ/m2, which is 165% higher than that of PA6/GF, and the UL‐94 test reaches V‐0 level. The findings of the study highlight the potential of PDAP and PDFP to act as dual‐function modifiers. These modifiers can considerably ameliorate both the impact resistance and flame retardancy of PA6 and PA6/GF composites. Such dual enhancement surpasses the typical trade‐offs seen in conventional composites, indicating a constructive direction for future material innovation.Highlights Polyphosphazenes simultaneously enhance PA6's toughness & flame resistance. Distinct flame retardant mechanisms found in PDAP and PDFP. GF presence alters PDAP and PDFP's flame retardant efficacy. PDAP shows superior flame resistance in GF‐reinforced PA6 composites. Without GF, PDFP outperforms PDAP in enhancing flame retardancy.

3-Pentadecylphenol (PDP) as a Novel Compatibilizer for Simultaneous Toughened and Reinforced PA10,12 Composites.

The utilization of polyamide 10,12 (PA10,12) composites in various industries has been limited constrained by their inherent low toughness, making it a challenge to achieve a balance between toughness and structural integrity through conventional elastomer addition strategies. Herein, we introduce a straightforward method for the concurrent toughening and reinforcement of PA10,12 composites. This is accomplished by blending polyolefin elastomer (POE) and 3-pentadecylphenol (PDP) with the PA10,12 matrix. The incorporation of 5 wt% PDP effectively blurred the PA10,12/POE interface due to PDP's role as a compatibilizer. This phenomenon is attributed to the formation of intermolecular hydrogen bonds, as evidenced by Fourier Transform Infrared Spectroscopy (FTIR) analysis. Further investigation, using differential scanning calorimetry (DSC), elucidated the crystallization thermodynamics and kinetics of the resulting binary PA10,12/POE and ternary PA10,12/POE/PDP composites. Notably, the crystallization temperature (Tc) was observed to decrease from 163.1 °C in the binary composite to 161.5 °C upon the addition of PDP. Increasing the PDP content to 10% led to a further reduction in Tc to 159.5 °C due to PDP's capacity to slow down crystallization. Consequently, the ternary composite of PA10,12/POE/PDP (92/3/5 wt%) demonstrated a synergistic improvement in mechanical properties, with an elongation at break of 579% and a notch impact strength of 61.54 kJ/m2. This represents an approximately eightfold increase over the impact strength of unmodified PA10,12. Therefore, our work provides the potential of PDP as a compatibilizer to develop nylon composites with enhanced stiffness and toughness.

Preparation of multistage porous polymer nanocomposites and its application in architectural design

In order to solve the problem that the toughness (impact strength) of the traditional elastomer toughening will decrease its rigidity (modulus) while improving the toughness (impact strength) of the material, the multi-porous nano-cacO3/polymer composite and its application in building plastics were proposed. In this essay, the mechanical properties of nano-caco3/PVC/CPE and nano-caco3/PP/SBS composites are studied. The results showed that the notch impact strength increased by 15.8 % from 46.8 kJ/m2 to 54.2kJ/m2 when two nano-cacO3 was added into the PP/SBS blend system, indicating that nano-cacO3 also toughened PP to some extent. ConclusionNano Ca-CO3 has remarkable toughening effect on PVC blending system, and also has certain toughening effect on PP blending system. The profile with nano-cacO3 added can ensure the impact performance of low temperature drop hammer, while the notched impact strength, tensile strength, elongation at break and flexural modulus of the simply supported beam are significantly improved compared with the profile without nano-cacO3 added. The application of nano CaCO3/PVC/CPE composites in the profile of PVC doors and Windows is studied.

Structural Optimization of PA12/MVQ@POE-g-MAH Ternary Composite for Superior Toughness and Low-Temperature Resistance.

To enhance the low-temperature toughness and resistance of the engineering plastic polyamide PA12, this study introduces novel PA12/MVQ@POE-g-MAH ternary composites using a two-step process and dynamic curing. Analytical results indicate that incorporating MVQ@POE-g-MAH into the PA12 matrix markedly enhances its toughness and heat resistance. As the MVQ@POE-g-MAH content increases, the elongation at break of PA12 composites significantly expands from 52.83% to 204.69%, and the notch impact strength escalates from 8.69 to 74.34kJ m-2. In addition, the brittleness temperature of PA12 decreases from -59.5 to -67.0°C. Experimental findings confirm that POE-g-MAH is dispersed at the interface between MVQ and PA12, creating an encapsulated structure of MVQ@POE-g-MAH. This enhancement significantly broadens the potential applications of PA12 by improving its toughness, and resistance to both low and high temperatures, as well as impact endurance.

Recyclability of elastomer toughened recycled poly(ethylene terephthalate): The effect of grinding-extrusion-injection moulding on the mechanical and morphological properties of the blend

Reprocessing potential of recycled poly(ethylene-terephthalate) (RPET)/ethylene-butyl-acrylate-glycidyl methacrylate (EBA-GMA) blends was investigated. PET flakes from food packaging were compounded with 0, 5, 10, 15 and 20 % EBA-GMA. Injection moulded specimens were produced, and some of the specimens were grinded, and reproduced to simulate real reprocessing. It was revealed by scanning electron microscopy that the distribution and particle size of the elastomer did not change notably after recycling. Noticeable degradation of the polymer matrix was observable after every processing step. Such deterioration of PET resulted in higher crystallinity and rigid amorphous fraction, as found by differential scanning calorimetry, which ultimately led to higher storage modulus, while the notched impact strength and elongation at break decreased. Nevertheless, the mechanical performance of the reprocessed RPET/EBA-GMA blends still significantly outperforms that of the neat PET recyclate. The degree of chain breakage was found to be the primary factor determining the recyclability of RPET/EBA-GMA blends.