Motion Of Polymer Chains Research Articles

Li-Ion Nanorobots with Enhanced Mobility for Fast-Ion Conducting Polymer Electrolytes

Ion transport in known polymer electrolytes highly depends on the segmental motion of polymer chains and they have low ionic conductivity due to a single-ion transport pathway. Novel design paradigms...

Effect of Styrene Concentration on Tensile Properties of Styrene-Acrylate Films

Abstract Due to an increasing awareness of environmental protection, waterborne coatings have replaced solvent-borne ones. The waterborne styrene-acrylate dispersion was successfully synthesized using emulsion polymerization. In this work, the emulsion was composed of Butyl Acrylate (BA) and Styrene (Sty) at different ratios. FTIR spectra confirmed the successful copolymerization of BA and Sty. Additionally, it was observed that all emulsions exhibited a consistent hydrodynamic diameter (120 nm to 140 nm), polydispersity index (between 0.030 and 0.050), and zeta potential (-40 mV to -60 mV). Thus, the BA/St ratio did not impact particle growth during emulsion polymerization. Furthermore, an increase in Sty concentration raised the glass transition temperature (Tg) of the films from 10.8 °C to 30.8 °C. This is attributed to Sty being a high Tg polymer, contributing to a rigid monomer that could enhance rigidity and restrict the movement of polymer chains. Additionally, the tensile strength of the dispersion films increased with the increase in Sty concentration, from 3.01 MPa to 5.88 MPa. Interestingly, the elongation at break did not significantly change as the St concentration increased, dropping by 15%. The investigation to aid in establishing relationships between the monomer concentration and mechanical properties of styrene-acrylate films.

Luminous Fish‐Inspired Hydrogels with Underwater Long‐Lived Room Temperature Phosphorescence

AbstractSome marine animals form long‐lived luminescence for predation, communication, camouflage, and anti‐predation. These marine animals demonstrate soft nature, sustainable glowing, and underwater emission, which are difficult to achieve in synthetic room temperature phosphorescence (RTP) materials. Inspired by these marine animals, here the study reports RTP hydrogels that show long‐lived phosphorescence (lifetime >500 ms and afterglow >10 s) in water. Exceptional underwater mechanical properties are simultaneously achieved, including tensile strength of 5.1 MPa, tensile strain of 452%, and toughness of 19.3 MJ m−3. The key to this achievement lies in the in situ phase separation microarchitecture formed between polyacrylamide (PAM) and its partial hydrolysates, which confines the motions of polymer chains and protects vulnerable triplet excitons from quenching of water. Such a strategy shows the merits of facile fabrication without laborious synthesis. In addition, these RTP hydrogels offer repeatable photoprinting and highly stability in water, providing a versatile platform for underwater applications of RTP materials, including information encryption and camouflage of marine animals.

Antidehydration and Stable Mechanical Properties during the Phase Transition of the PNIPAM-Based Hydrogel for Body-Temperature-Monitoring Sensors.

Poly(N-isopropylacrylamide) (PNIPAM) enhances the reversibility and responsiveness of wearable temperature-sensitive devices. However, an open question is whether and how the hydrogel design can prevent adhesive performance loss caused by phase-transition-induced dehydration and unstable mechanical properties between devices and human skin and reduce interfacial failure. Herein, a gelatin-mesh scaffold-based hydrogel (NAGP-Gel) is constructed to inhibit dehydration and volume change, leading to stable mechanical properties, superior adhesiveness, and thermal sensing sensitivity during the phase transition. NAGP-Gel enhances the polymer chains-water interaction and weakens the degree of aggregation of polymer chains-chains, improving antidehydration properties under 45 °C conditions that are higher than the lower critical solution temperature (LCST; i.e., ∼32 °C). The mesh scaffold greatly restricts the phase-transition-induced polymer chain movement and maintains the mechanical performance. In a 60 °C environment, the maximum water loss and volume retention ratio of NAGP-Gel are only 3.58% and 97.3%, respectively. Additionally, NAGP-Gel serves as a temperature sensor, producing a stable thermal-electrical signal within the LCST range. It also can be assembled into an electronic device enabling the transmission of information and recognition of sign language via Morse code. This work broadens the application of PNIPAM in constructing intelligent hydrogels and opens the door to exploring emerging hydrogels for temperature-monitoring applications.

Dynamic surface gratings for optical encryption: A simple approach based on azobenzene photoisomerization and solvent engineering

Dynamic diffraction gratings are optical devices that allow for non-mechanical, non-contact and remote on-demand control, and have garnered significant interest in optical encryption. Azobenzene materials are ideal materials for developing dynamic gratings owing to the advantages of fast photo isomerization and good reversibility. It is still challenging to precisely fabricate ordered periodic gratings on the surfaces of azobenzene materials. Here, controllable dynamic grating patterns were successfully fabricated by mask exposure and solvent engineering on azobenzene polyamide acid (PAA-Azo)-solvent system. The movement and mass migration of polymer chains can be regulated by modulating the intermolecular hydrogen bonding and free volume based on different solvents and solvent contents within the system, resulting in the formation of surface gratings with customizable morphology and light-splitting ability. Finally, by regulating the periodicity and amplitude of gratings, colorful dynamic patterns were obtained to monitor the expiration of light-sensitive and short shelf-life products, based on the azobenzene polyamide acid (PAA-Azo)-solvent system. This work provides a new and simple approach for controllable preparation of high-regularity and high-performance dynamic gratings.

A uniform understanding of polymer crystallization models: Diffusion and conformational transition model

In the last 100 years, the study of polymer crystallization theory has achieved many breakthroughs, and a large number of models and theories have been proposed. However, each of them can only partially explain the crystallization behavior of polymers. A uniform understanding of polymer crystallization remains a huge challenge. In this paper, we try to understand the crystallization of polymers from the motion of polymer chains, and a universal model, the diffusion and conformational transition (DCT) model, is proposed. The DCT model can provide a unified understanding of the current polymer crystallization models. We propose that the nature of polymer crystallization is the synergy and competition between the diffusion (D) and the conformational transition (CT) processes. Moreover, by dividing the types of D and CT into D1 to D3 and CT1 to CT6, respectively, the homogeneous nucleation process and the growth of polymer crystals on the surface of an existing crystal are discussed. Some important results on the number of stems for critical nuclei, the type of nucleation, the origin of the conformation of chain segments on the end surface of lamellar crystals, etc. have been achieved. These results not only provide a good explanation of the experimental findings in the literature, but also contain some new findings. The DCT model may further be used to resolve disputes, explain and predict new phenomena, and teach beginners in polymer crystallization in the future.

Proton Hydrogel-Based Supercapacitors with Rapid Low-Temperature Self-Healing Properties.

Hydrogel-based supercapacitors are an up-and-coming candidate for safe and portable energy storage. However, it is challenging for hydrogel electrolytes to achieve high conductivity and rapid self-healing at subzero temperatures because the movements of polymer chains and the reconstruction capability of broken dynamic bonds are limited. Herein, a highly conductive proton polyacrylamide-phytic acid (PAAm-PA) hydrogel electrolyte with rapid and autonomous self-healing ability and excellent adhesion over a wide temperature range is developed. PA, as a proton donor center, endows the hydrogels with high conductivity (102.0 mS cm-1) based on the Grotthuss mechanism. PA can also prevent the crystallization of water and form multiple reversible hydrogen bonds in the polymer network, which solves the dysfunction of self-healing hydrogels in a cryogenic environment. Accordingly, the hydrogel electrolytes demonstrate fast low-temperature self-healing ability with a self-healing efficiency of 79.4% within 3 h at -20 °C. In addition, the hydrogel electrolytes present outstanding adhesiveness on electrodes due to the generation of hydrogen bonds between PA and activated carbon electrodes. As a result, the integrated hydrogel-based supercapacitors with tight bonding electrode/electrolyte interface deliver a 139.5 mF cm-2 specific capacitance at 25 °C. Moreover, the supercapacitors display superb self-healing ability, achieving 92.1% of capacitance recovery after three cutting-healing cycles at -20 °C. Furthermore, the supercapacitors demonstrate only 6.4% capacitance degradation after 5000 charging-discharging cycles at -20 °C. This work provides a roadmap for designing all-in-one flexible energy storage devices with excellent self-healing ability over a wide temperature range.

Surface effect-tailored polymer membranes with an integrated extra-thin separation layer for robust nanofiltration

Nanofiltration (NF) technology has been keeping an unassailable lead in molecular and ionic separations. However, current polymeric NF membranes fall short of expectations in selectivity and stability when it comes to some heavy-duty organic, alkaline, and acidic environments. In this work, an asymmetric poly(ether sulfone) (PES) NF membrane with an integrated and extra-thin separation layer was developed by utilizing a thermal treatment method based on the polymer surface effect. A PES ultrafiltration membrane with a porous patterning surface was first fabricated by nonsolvent induced phase separation, and then thermally annealed at 5 degrees lower than its glass transition temperature to fully activate the motion of surface polymer chains to kinetically heal surface pores. The healing mechanism of surface pores was confirmed as the thermodynamic minimization tendency of surface energy driven by the advanced mobility of PES chains on the surface. The formed separation layer was 88 nm in thickness, far less than conventional integrated asymmetric membranes and comparable to current thin-film composite (TFC) membranes. As expected, the membranes had high rejection to organic molecules and inorganic salts with a molecular weight cut-off of around 600 Da, while maintaining a competitive water permeance up to 8 L m−2 h−1 bar−1 to current TFC membranes. Further, they demonstrated high acid tolerance without performance decline during a 30-h-long test after being immersed in 8 wt% H2SO4 aqueous solution for 24 h. This work offers a new strategy to develop high permeability, selectivity, and environmental-resistance NF membranes to achieve efficient molecular and ionic separations in extreme conditions.

Enhancing the electrochemical properties of biopolymer composites using starch‐graphene nanoplatelets

AbstractThe study presents the ideal distribution of graphene nanoplatelets (GNP) within the thermoplastic starch (TPS) matrix significantly elevated the thermal and electrical conductivities, as well as the electrochemical efficiency of the biocomposites. Additionally, the incorporation of GNP resulted in an increased thermal stability for the TPS, as indicated by the elevated temperatures required for maximum degradation. The biocomposites exhibited a self‐aligned layered structure, creating conductive pathways and enhancing electron conduction. An electrical conductivity increased as the concentration of GNP increased, with the highest conductivity observed on the top and bottom surface with the value of 4.23 × 10−7 S/m and 3.92 × 10−6 S/m when 12 wt% of GNP was added. The presence of hydroxyl groups in TPS facilitated the formation of hydrogen bonds with GNP, preventing GNP from stacking and forming a more uniform conductive network within the film. The addition of 15 wt% GNP also improved the capacitive performance of the TPS matrix, as evidenced by higher current responses and larger quasi‐rectangular areas in the cyclic voltammetry curves compared to neat TPS. The Nyquist plots which are illustrated impedance data showed that the TPS film with 12 wt% GNP exhibits the smallest semicircle, indicating the highest conductivity which is suggested that GNP improves charge transfer compared to pure TPS.Highlights Optimal dispersion of GNP enhanced the biocomposite's properties. The electrical conductivity increases with the GNP content until 12 wt%. TPS/GNP self‐aligned layered improved conduction and capacitive behavior. GNP improved thermal stability by restricting polymer chain movement. Electrochemical impedance shows improved properties of TPS/GNP.

A study of EMI shielding efficiency, dielectric, and impedance properties of polymer nanocomposites reinforced with Graphene nanoplatelets, montmorillonite, and copper oxide nanoparticles

ABSTRACT In the present study, polyvinylchloride (PVC) and polymethyl methacrylate (PMMA) blended nanocomposites comprised of graphene nanoplatelets (GNPs), montmorillonite (MMT), and copper oxide (CuO) nanoparticles were prepared through solvent casting approach. The structural and morphological measurements confirmed the presence and dispersion of nanofillers in the polymeric chains. Thermo-gravimetric analysis (TGA) and differential-scanning calorimetry (DSC) investigations suggested the improved thermal stability for nanocomposite with 1.5 wt% GNPs loading having minimum weight loss and reduction in Tm due to the presence of GNPs, MMT, and CuO acting as a barrier to oxygen molecule diffusion and polymer-chain movement in the nanocomposite. The dielectric and impedance properties of PVC/PMMA/MMT/GNP/CuO nanocomposite investigated in 1 Hz to 20 MHz frequency range and at room temperature have shown improved dielectric constant upto 90.59 in 1 Hz frequency. The σac measures to be improved by 0.0034 (S/m) after adding GNPs, MMT, and CuO resulted from the interfacial polarization effect. The cole–cole plot investigations have shown the formation of semicircles for higher nanofiller loadings of nanocomposite. A drastic improvement in the SETotal was observed from lower to higher nanofiller concentrations. The total SE obtained for the nanocomposite with 2.5 wt% GNPs is upto 5 dB in 8–12 GHz range with absorption dominant nature of nanocomposite.

On modelling strain gradient viscoelasticity of polymer nanocomposites

Theories of generalized continuum mechanics have found great success in the analysis of nanostructures. However, there exists no work on analysing composites whose constituents are generalized continua. The present work fills this gap and studies the strain gradient viscoelasticity of polymeric nanocomposites. The key problem is to assign the nonclassical boundary condition of the representative volume element (RVE). To resolve it, a perturbation field is superposed on the homogeneous displacement boundary condition. The wavelength of perturbation is comparable to the strain gradient characteristic length. Simulations to obtain the macroscopic effective mechanical properties are performed, which agree well with the experimental data. The frequency dependence of the perturbation field is revealed, and it has a clear physical interpretation in terms of the segmental motions of polymer chains.

Combining dip-coating and rotate-drying to preparation of PDMS on SiC tubular support with macropore for high pervaporation performance

High-performance polydimethylsiloxane (PDMS)/ceramic tubular pervaporation membranes have potential in industrial separation applications, but realizing the preparation of PDMS layer on the ceramic supports with micrometer-scale pore size (0.8 μm or 4.3 μm) for improving performance remains a challenge. We report a strategy (combined dip-coating and rotate-drying, DCRD) to preparation of PDMS on silicon carbide (SiC) tubular support with macropore. Response surface methodology was employed to optimize the dip-coating process, and the influence of friction velocity on tubular composite membranes was investigated. The results indicate that pulling speed, casting solution viscosity, and their interaction have significant effects on the pervaporation performance of PDMS/SiC tubular composite membranes. Moreover, increasing friction velocity results in uneven PDMS layer thickness, which in turn impacts the pervaporation performance of the composite membrane. Furthermore, the rigid structure of SiC restricts the movement of PDMS polymer chains, enabling the composite membrane to maintain stable pervaporation performance at higher isobutanol feed concentrations (3 wt%) or elevated feed temperatures (60 °C). After continuous operation for 200 h, the developed PDMS/SiC tubular composite membrane consistently maintained the total flux of 650 g m−2 h−1 and the separation factor of 39 for isobutanol/water. Eventually, this novel fabrication method offers new insights into the preparation of various other organic-inorganic tubular composite membranes.

Effects of network structure on the viscoelastic creep and delayed fracture of polyelectrolyte elastomers

The past decade has witnessed a significant surge in the field of stretchable ionotronics, wherein stretchable ionic conductors play an essential role. Polyelectrolyte elastomers have been featured as the most promising stretchable ionic conductors for engineering practice owing to their leakage-free nature. However, the inherent viscosity of the ionized polymer networks confounds the responses of the materials thus hampering the applicability of the devices. Therefore, it is of significant importance to study the viscoelastic behaviors and understand the overlayed molecular mechanism. In this work, we study the effects of network structure on the viscoelastic creep and delayed fracture of polyelectrolyte elastomers. We design and synthesize poly(1-[2acryloyloxyethyl]-3-butylimidazolium bis(trifluoromethane) sulfonimide-co-methyl acrylate) elastomer and tune the network structure by changing the covalent crosslink density and the molar ratio between the ionic segment and the neutral segment, which are the two most crucial structural parameters. We perform tensile and creep tests for polyelectrolyte elastomers of different compositions and interpret the creep results, with emphasis placed on the effects of applied stress and strain hardening. In general, the creep deformation is mitigated with increasing covalent crosslink density and the molar ratio between the ionic segment and the neutral segment, suggesting that creep is mainly due to the breakage of ionic bonds and the slippage and movement of polymer chains. This work promotes the understanding of the viscoelastic behaviors of polyelectrolyte elastomers and provides insights for tailoring the mechanical properties through the rational design of polymer networks, which is expected to facilitate the development of next-generation stretchable ionotronic devices.

Thermoplastic polyimide with low dielectric properties enabled by the 2,2′‐spirobifluorene group

AbstractThermoplastic polyimides (TPIs) have melt‐processability and adhesive ability, besides the intrinsic advantages of polyimides. To meet the requirements of applications in high‐frequency communication, TPIs with low dielectric constant (Dk)/dielectric loss factor (Df) at high frequency are also desirable. Enhancing the rigidity of polymer chains and simultaneously intermolecular interaction are effective ways to ensure low Dk/Df, which also benefit to heat resistance. However, it is not conducive to thermoplasticity, due to limited movement of polymer chains. To balance the trade‐off between them, we introduce noncoplanar 2,2′‐spirobifluorene groups to modify the rigidity of polymer chains and regulate the twist between electron‐donor moieties (diamine units) and electron‐acceptor moieties (dianhydride units). It leads to rigid polymer chains, which benefits to good heat resistance and dielectric properties. Meanwhile, the resultant irregular chain structure is difficult to crystallize, which results in thermoplasticity.

Power factor enhancement in benzodithiophene-based conjugated polymers through controlling solution-state aggregation

Controlling solution-state aggregation of conjugated polymers is crucial for tuning solid-state morphology as well as electrical properties. However, the effect of solution-state aggregation on their thermoelectric performance is rarely reported. Using a series of poly(benzodithiophene-alt-thiophene) conjugated polymers (PBDT-Fm, m is the content of semi-fluorinated groups in polymer chain), the polymer solution aggregations were tuned by the evaporation temperature, which has achieved optimized P(BDT-Fm) films with high degree of molecular order, homogeneous polymer aggregates and small crystalline domains, leading to dramatic enhancement in thermoelectric performance. Compared with the naturally dried polymer films, the heated evaporating process led to at least 49-fold and 15-fold enhancement in the conductivity and power factor, respectively. Optical spectroscopy and microcosmic morphology have shown that the strong molecular motion of polymer chains at high evaporation temperature would disaggregate the polymer pre-aggregations in solution and assist the formation of orderly packed microstructures in solid state, leading to a significant increase in the power factor. Through controlling solution-state polymer aggregations, PBDT-F15 achieved the power factors up to 7.74 ± 0.01 µW m−1 K−2, which is among the highest values in the reported benzodithiophene-based conjugated polymers, highlighting the importance of controlling polymer solution aggregation in optimizing thermoelectric performance.

Shear relaxation behavior for degraded polypropylene melt in torque rheometer

AbstractShear relaxation behavior for polymer melt exists in different processing techniques and influences the dimensional accuracy and production efficiency of polymer products. A micro physical and mathematical model based on microstructure of polymer chains and processing parameters was established and verified by experimental results obtained from a torque rheometer. The shear relaxation time of polypropylene degraded by di‐tert‐butyl peroxide was characterized with torque rheometer. The effects of microstructure and processing parameters on the shear relaxation time was investigated. The results showed that a wider molecular weight distribution could result in a decrease in shear relaxation time and polypropylene chains with higher molecular weight were more sensitive to molecular weight distribution. The shear relaxation time declined exponentially with shear rate and increased with internal pressure. The temperature could enhance the movement of polymer chains and reduce the shear relaxation time linearly, but polypropylene with lower molecular weight was less sensitive to temperature. The insight obtained from the mathematical and experimental results can be profoundly applied in practical process control to manufacture product with better dimensional stability and production efficiency for viscoelastic polymer.Highlights A physical and mathematical model based on microstructure and processing parameters of molecular chains was established to explore the shear relaxation mechanism. Shear relaxation time of polypropylene degraded by di‐tert‐butyl peroxide was characterized with the help of torque rheometer. The effects of microstructure and processing parameters on shear relaxation time was investigated to optimize the manufacturing of polypropylene products.

Flow Behavior of Entangled Polymer Nanoparticle Composites in a Nanotube: Insights into Jamming State.

Using molecular dynamics simulations, this study investigates the equilibrium properties and flow behaviors of entangled polymer nanoparticle composites (PNCs) within a nanotube. The results show that the density distribution of nanoparticles (NPs), displacement of polymer chains and NPs, and the moduli of PNCs remain relatively unaffected when NP volume fractions (ΦN) ≤0.10. However, the flow behavior of entangled PNCs deviates from the ideal parabolic profile seen in unentangled PNCs, displaying plug-like flow characteristics with a significant platform region, indicating the presence of shear bands. Interestingly, entangled PNCs at intermediate ΦN values undergo a significant alteration in NP distribution under steady flow, resulting in notable NP aggregation. At ΦN = 0.30, a distinct change in the static structure of PNCs occurs, reducing the equilibrium distance between neighboring NPs. Consequently, the motion of both polymer chains and NPs becomes restricted, leading to an increase in the moduli of PNCs resembling solid-like behavior. Additionally, the entangled PNCs experience a complete absence of flow, indicating the entry into a jamming state. This study contributes to the understanding of PNCs flow behavior and provides insights into fundamental aspects and practical implications of PNCs.

Suppressing Dielectric Loss in MXene/Polymer Nanocomposites through Interfacial Interactions.

Although numerous polymer-based composites exhibit excellent dielectric permittivity, their dielectric performance in various applications is severely hampered by high dielectric loss induced by interfacial space charging and a leakage current. Herein, we demonstrate that embedding molten salt etched MXene into a poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE))/poly(methyl methacrylate) (PMMA) hybrid matrix induces strong interfacial interactions, forming a close-packed inner polymer layer and leading to significantly suppressed dielectric loss and markedly increased dielectric permittivity over a broad frequency range. The intensive molecular interaction caused by the dense electronegative functional terminations (-O and -Cl) in MXene results in restricted polymer chain movement and dense molecular arrangement, which reduce the transportation of the mobile charge carriers. Consequently, compared to the neat polymer, the dielectric constant of the composite with 2.8 wt % MXene filler increases from ∼52 to ∼180 and the dielectric loss remains at the same value (∼0.06) at 1 kHz. We demonstrate that the dielectric loss suppression is largely due to the formation of close-packed interfaces between the MXene and the polymer matrix.

Influence of Nano-CeO2 and Graphene Nanoplatelets on the Conductivity and Dielectric Properties of Poly(vinylidene fluoride) Nanocomposite Films.

Novel three-phase polymer nanocomposites (PNCs) based on cerium oxide (CeO2) nanoparticles (NPs) and graphene nanoplatelets (GNPs) incorporated in a poly(vinylidene fluoride) (PVDF) matrix were formulated using a solution-casting approach. To understand the structural and morphological features of PVDF/CeO2/GNP nanocomposites (NCs), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) analyses were accomplished. The PVDF/CeO2/GNP NCs displayed improved thermal stability which resulted from strong bonding between GNPs and CeO2 NPs and restriction of the polymer chain movement. The introduction of CeO2 NPs and GNPs within the PVDF matrix and good synergy between CeO2 NPs and GNPs led to variable mechanical properties of the prepared NCs. The PVDF/CeO2/GNP NCs portrayed reduced thermal stability, which could be due to the increased mobility of PVDF chains imposed by GNPs leading to the formation of volatile degradation products. Moreover, PVDF/CeO2/GNP NCs exhibited good electrical conductivity and high dielectric permittivity. The obtained dielectric permittivity value for the PVDF/CeO2/GNP NCs was 3-fold greater than PVDF/CeO2 NCs, making these novel tertiary composite materials a probable candidate for energy-storage applications.

Significantly enhanced laser trapping and heating of carbon nanotube/carbon fibre hierarchical composites for efficient laser-assisted automated fibre placement

Laser-assisted automated fibre placement (LAFP) process is promising for manufacturing large-scale thermoplastic composite parts. However, its laydown speed suffers from the near-infrared (NIR) laser reflection from carbon fibres (CFs) and the high specific heat capacity of prepregs. Herein, the light-trapping carbon nanotube (CNT) forest was grown on CFs using a low-cost flame synthesis process, followed by its embedding in the poly-ether-ether-ketone (PEEK) matrix to produce CF/PEEK/CNTs prepregs with simultaneously enhanced laser absorption and reduced specific heat capacity. Spectroscopic analysis shows that CNTs reduce the NIR reflectance of prepregs due to enhanced light-trapping efficiency with hierarchical CNT/CF structures, further evidenced by a transition from diffuse reflection to specular reflection. Additionally, CNTs reduce 19 % of the specific heat capacity by restricting polymer chain movement. Therefore, the hierarchical structure increases the heating rate and maximum temperature of CF/PEEK prepregs by 18.5 % and 16.0 %, respectively, under 1080 nm laser radiation during the LAFP process.