Induced Energy Dissipation Research Articles

Oxygen-termination effect on the surface energy dissipation in diamond MEMS

Single-crystal diamond (SCD) microelectromechanical systems (MEMS) resonators with lower energy dissipation and higher quality (Q) factors have always been pursued for the development of high-sensitivity and high signal-to-noise ratio (SNR) MEMS sensors. The intrinsic loss such as the crystal quality and extrinsic loss of clamping loss have been examined to improve the Q factors of SCD MEMS resonators. Nevertheless, the surface termination induced energy dissipation has rarely been known due to the lack of high crystal quality diamond resonators and in-situ characterization. Here we examine the effect of oxygen-termination on the surface energy dissipation of SCD cantilevers by in-situ heating these cantilevers in a high vacuum chamber. After thermal treatment of the cantilevers at 933 K, the Q factor of the cantilever is improved from 2.8x105 to 3.3x105 (i.e. the 120 μm-long). The resonance frequency increase confirms the desorption of surface adsorbates. Compared to silicon, on which a native solid-state oxide exists, the surface oxygen-termination induced loss in diamond MEMS is much smaller. The non-existence of native oxides on diamond surface is an obvious merit toward ultra-high Q factor MEMS resonators.

Unveiling the role of pore characteristics in sludge dewatering: Visualization by Nano-CT and micromodel study

The solid-liquid separation is an indispensable and primary link in the process of sludge treatment and disposal. The past research was focused primarily on the technique explorations of sludge dewatering and always disregarded the internal pore structure and water migration behavior in sludge. In this work, the real three-dimensional pore structure of sludge was obtained by Nano-CT. Based on this, a pore-scale heterogeneous sludge micromodel was firstly presented, and the water flooding experiment was carried out to visualize the water migration behavior. The results showed that the sludge structure transformed from sheet-like floc to microsphere particles, and then agglomerated into large globular granules during anaerobic ammonia oxidation. And the equivalent pore size increases from 342 μm to 617 μm, improving the sludge dewaterability characterized by capillary suction time (CST). The most significant implication of this work was revealing the critical role of invalid connected pore in sludge dewatering. Such pore was not contributed to fluid flow but the circulating vortex in it even induced energy dissipation, thus deteriorated the sludge dewaterability. This work may be helpful to understand the critical role of pore characteristic in water migration and shed light on the new dewatering techniques from the perspective of regulating sludge structure.

A material–structure-wave integrated hydro-viscoelastic model for floating composite structure with generalized boundary

A floating viscoelastic composite structure with generalized elastic constraints, in which the material–structure-wave interaction induces energy dissipation, is analyzed with a novel cross-scale integrated hydro-viscoelastic model. A double-level three-dimensional (3D) representative volume element model coupling mesoscale reinforced particles to a macroscale composite structure is established to obtain the structure's viscoelastic dynamic equation. Therefore, a hydro-viscoelasticity analytical model for floating composite structures with arbitrary elastic constraints under wave action is developed in the context of potential flow theory. In the process of solving the velocity potential, the dispersion equation of the water covered by the composite structure is derived. The hydrodynamic and mechanical behaviors of the floating composite structure, including the reflection coefficient, transmission coefficient, dissipation coefficient, deflection, shear force, and bending moment, are comprehensively calculated, which depend on the cross-scale integrated effects of wave action, structural features, material characteristics, and constraint combinations. This material–structure-wave integrated model would be useful to elucidate the hydro-viscoelastic dissipation mechanism of marine structures.

Numerical Simulations and an Updated Parameterization of the Breaking Internal Solitary Wave Over the Continental Shelf

AbstractThe breaking of internal solitary waves (ISWs) over slope‐shelf topography induces energy dissipation and enhances mixing. In this work, high‐resolution, laboratory‐scale simulations are employed to investigate the instability mechanisms and dissipation of ISWs. We find that the increasing nonhydrostatic pressure during deformation contributes to an adverse pressure gradient, which induces plunging flow for overturning. Shear instability and convective instabilities trigger wave breaking. Wave‐induced vortexes induce strong shearing and enhance the dissipation of energy by 1–2 orders of magnitude larger than that which occurs under stable conditions. Furthermore, based on laboratory results, we evaluate two commonly used parameterizations (Pacanowski & Philander, 1981, https://doi.org/10.1175/1520-0485(1981)011<1443:povmin>2.0.co;2, i.e., PP81; Klymak & Legg, 2010, https://doi.org/10.1016/j.ocemod.2010.02.005, i.e., KL10) in coarser‐resolution global ocean models by modifying the horizontal resolution from 100 grids every wavelength to approximately 30. The results show that PP81 and KL10 can both improve the estimation of the energy loss, but can only depict strong shear within the pycnocline and bottom boundary regions, respectively. Finally, an updated parameterization is presented that can effectively describe the strong shear in two regions during wave breaking. The flow field and dissipation are more consistent with the laboratory results using the new parameterization. This study improves the understanding of the mixing parameterizations in simulating the continuous processes of strong internal wave breaking.

Study on the influencing parameters of rough-strip energy dissipators of curved spillways based on orthogonal tests and numerical simulation

Abstract Rough-strip energy dissipators (R-SEDs) can be arranged at the bend bottom of curved spillways to dissipate energy and divert flow for bend flow. Using the entropy weight and TOPSIS methods, a multi-criteria evaluation system was established for comprehensive energy dissipation and flow diversion effects of R-SEDs. Orthogonal tests and numerical simulation were conducted to analyze factors affecting these effects (average R-SED height, R-SED angle, R-SED spacing, bend width, bend centerline radius and discharge flow rate). It was found that bend width and bend centerline radius significantly affected R-SEDs' energy dissipation effects. Average R-SED height, R-SED spacing and bend centerline radius significantly affected R-SEDs' flow diversion effects. Bend width, average R-SED height and bend centerline radius significantly affected R-SEDs' combined effects of energy dissipation and flow diversion. Their energy dissipation effects were larger than the flow diversion effects. R-SEDs can effectively alleviate adverse hydraulic phenomena in curved spillways. With the recommended parameters, R-SEDs showed the best performance, with the energy dissipation rate increasing by 18.67% and the water surface superelevation coefficient decreasing by 26.14%. The accuracy of the multi-criteria evaluation system was verified. This study can provide a reference for the R-SED design of similar curved spillways.

Numerical Investigation of Gas Dynamic Foil Bearings Conjugated with Contact Friction by Elastic Multi-Leaf Foils

With increasing demand for load capacity and dynamic responses, the new generation of Gas Dynamic Foil Bearings (GDFB), assembled from preloaded elastic multi-leaf foils, has been put forward. It exhibits steady and dynamic characteristics that are more sensitive to the contact friction produced by foil–foil bearings and the housings of foil bearings, distinguishing its response to rigidity from those of classic bearings. This study aims to employ numerical simulations to explore GDFBs conjugated with contact friction using elastic multi-leaf foils. A numerical method with Bidirectional Fluid–Structure Interactions (BFSIs), which strengthens the steady and dynamic characteristics of GDFBs, has been developed. The results showed that the distribution of steady stiffness was closely associated with the configuration of the foil assembly and the state of contact friction. The maximum steady stiffness occurred near the key blocks and was accompanied by the support of bump foils. The contact friction increased the stiffness of the foil assembly, which was unfavorable to its operational stability, and the GDFB was prone to rigidity. The contact friction hindered the pull-back of the top foils near the negative pressure area. An increase in the rotational speed and eccentricity increased the load capacity while decreasing the operational stability. The maximum pressure of the gas film was inconsistent with the maximum deformation along the circumferential direction because of the configuration of the foil assembly. The contact friction induced energy dissipation, whereas increases in the integrated stiffness inhibited loss. The fixed constraint of the key block increased the dynamic cross-stiffness more than the contact constraint did, which was unfavorable to operational stability. The results obtained in this study are significant because they provide a physical basis for GDFBs and can be used to guide their operational optimization.

Evaluation of edge transport and core accumulation of tungsten for CFETR with EMC3-EIRENE and STRAHL

The edge transport and core accumulation of tungsten (W) particles on China Fusion Engineering Test Reactor (CFETR) have been studied by integrated modelling consisting of EMC3-EIRENE and STRAHL codes. The edge transport and power dissipation of W particles are simulated by EMC3-EIRENE. An in–out asymmetry of W(1–28)+ ions density has been revealed in the in- and out-board divertor regions. This is mainly due to the stronger reversal flow velocity of W ions at the outboard divertor. The upward flow of W ions near the separatrix leads to a moderate W impurity leakage from the divertor on CFETR compared to the existing full W device ASDEX Upgrade due to the high plasma density near the CFETR divertor targets. Further, the density distribution and radiation loss of W ions in the core region are investigated by STRAHL code. The high charge-state W(29–60)+ and W(61–74)+ ions mainly reside in the regions of ΨN = 0.20–0.98 and 0.00–0.90 (ΨN is the normalized poloidal magnetic flux), respectively. The W induced energy dissipation in different regions is assessed according to both STRAHL and EMC3-EIRENE simulations. Particularly, the impacts of the W core radiation on the operation regime are discussed according to the H-mode threshold scaling law proposed by Martin et al (2008 J. Phys.: Conf. Ser. 123 012033) for the baseline plasma on CFETR. Further, parameter studies on the pinch velocity (v imp) and diffusion coefficient (D imp) have been performed to check their impacts on the operation regime of CFETR. A three-fold increase of v imp/D imp results in a higher W core energy loss, which can lead to the transition from H-mode back to L-mode.

Energy dissipation of mechanical metamaterials composed of multilayer buckling elements

The effect of layer number, buckling sequence and drive velocity on energy dissipation per buckling event of mechanical metamaterials composed of representative volume element (RVE) is studied. Buckling behaviors of a single RVE encompassing buckling beams are investigated based on an approximate model. The metamaterials are modeled as a tandem model composed of identical RVEs. The buckling behavior can not induce energy dissipation if for the proposed structure. As or drive velocity increases, energy can be dissipated during elastic buckling. Besides, the dissipated energy per buckling event gradually decreases during one complete loading and unloading process.

Optimization on fishing net porosity of twin pontoon floating breakwater in waves

Chaotic process in wave passing through pores on the attached fishing net between twin pontoons of floating breakwater (TPFB) may lead to several severe problems relating to the hydrodynamic performance of such coastal structure. In presence of relatively fine pores, the wave transmission coefficient (Kt) tends to diminish while the reflection coefficient (Kr) will likely increase, or vice versa for coarse ones. The circumstance requires a complete design optimization study into obtaining an optimum porosity. This paper presents optimization on the fishing net porosity (n) of TPFB using artificial intelligence (AI) model. Here, a multi-objective evolutionary algorithm with various genetic parameters is proposed to search for optimum n ratio through primarily minimizing transmission (Kt) and reflection coefficients (Kr) while maximizing energy dissipation coefficient (Kd). In addition, a computational fluid dynamic (CFD) programme is developed using an extended Reynolds Average Navier-Stokes (RANS) solver for a solid-permeable obstacle. Several parameters such as wavelengths and porosity ratios including a set of optimization criteria, have been taken into account in the simulation, where the optimum solution is then selected from various populations. Meanwhile, the optimum result will be qualitatively evaluated, in which it is visualized by the characteristic patterns of induced energy dissipation. The results revealed that the optimization algorithm is effectively capable of determining global trade-offs between Kt, Kr, and Kd. As compared to the existing model, Kt and Kr decrease to less than 0.85 and 0.42 respectively, whereas Kd was increased up to 0.34 resulting in optimum hydrodynamics of TPFB indicated by further enhancement in the rate of energy dissipation across TPFB entanglement. For validation, the numerical model can fairly simulate well on the hydrodynamics of structure.

Detailed characterization of a laboratory magnetized supercritical collisionless shock and of the associated proton energization

Collisionless shocks are ubiquitous in the Universe and are held responsible for the production of nonthermal particles and high-energy radiation. In the absence of particle collisions in the system, theory shows that the interaction of an expanding plasma with a pre-existing electromagnetic structure (as in our case) is able to induce energy dissipation and allow shock formation. Shock formation can alternatively take place when two plasmas interact, through microscopic instabilities inducing electromagnetic fields that are able in turn to mediate energy dissipation and shock formation. Using our platform in which we couple a rapidly expanding plasma induced by high-power lasers (JLF/Titan at LLNL and LULI2000) with high-strength magnetic fields, we have investigated the generation of a magnetized collisionless shock and the associated particle energization. We have characterized the shock as being collisionless and supercritical. We report here on measurements of the plasma density and temperature, the electromagnetic field structures, and the particle energization in the experiments, under various conditions of ambient plasma and magnetic field. We have also modeled the formation of the shocks using macroscopic hydrodynamic simulations and the associated particle acceleration using kinetic particle-in-cell simulations. As a companion paper to Yao et al. [Nat. Phys. 17, 1177–1182 (2021)], here we show additional results of the experiments and simulations, providing more information to allow their reproduction and to demonstrate the robustness of our interpretation of the proton energization mechanism as being shock surfing acceleration.

CFD Based Non-Dimensional Characterization of Energy Dissipation Due to Verticle Slosh

We present the CFD based non-dimensional characterization of violent slosh induced energy dissipation due a tank under vertical excitation. Experimentally validated CFD is used for this purpose as an ideally suited and versatile tool. It is thus first demonstrated that a weakly compressible VoF based CFD scheme is capable of computing violent slosh induced energy dissipation with high accuracy. The resulting CFD based energy analysis further informs that the main source of energy dissipation during violent slosh is due liquid impact. Next, a functional relationship characterising slosh induced energy dissipation is formulated in terms of fluid physics based non-dimensional numbers. These comprised contact angle and liquid–gas density ratio as well as Reynolds, Weber and Froude numbers. The Froude number is found the most significant in characterising verticle violent slosh induced energy dissipation (in the absence of significant phase change). The validated CFD is consequently employed to develop scaling laws (curve fits) which quantify energy dissipation as a function of the most important fluid physics non-dimensional numbers. These newly developed scaling laws show for the first time that slosh induced energy dissipation may be expressed as a quadratic function of Froude number and as a linear function of liquid–gas density ratio. Based on the aforementioned it is postulated that violent slosh induced energy dissipation may be expressed as a linear function of tank kinetic energy. The article is concluded by demonstrating the practical use of the novel CFD derived non-dimensional scaling laws to infer slosh induced energy dissipation for ideal experiments (with exact fluid physics similarity to the full scale Aircraft) from (non-ideal) slosh experiments.

Preparation and properties of poly(L-lactic acid) blends with excellent low-temperature toughness by blending acrylic ester based impact resistance agent

Poly(L-lactic acid) (PLLA) blends with excellent low-temperature toughness and strength were prepared by melt compounding with acrylic ester based impact resistance agent (AEIR). The morphology, thermal properties, mechanical properties and biodegradability of the blends were investigated. Morphology observations revealed the blend was immiscible but had good compatibility with the dispersed phase size of about 200–300 nm. With the addition of AEIR, dramatic improvement in toughness of PLLA was achieved in a wide temperature range, especially at low temperatures the tensile strength was effectively remained. For the blend with 20 wt% AEIR, the tensile strength, elongation at break and impact strength were 51.6 MPa, 72% and 77.1 KJ/m2 at −20 °C, respectively, much greater than that reported. The calculated Tg of AEIR was lower than the test temperatures, and the brittle-tough transition occurred. The PLLA matrix demonstrated obvious shear yielding which induced energy dissipation and therefore lead to excellent toughness of the blends. Moreover, the biodegradation of PLLA was enhanced after blends preparation.

Brief introduction to flux pinning and vortex dynamics in high temperature superconductors

Superconductivity is achieved through macroscopic phase coherence; the charge carriers are Cooper pairs. In absence of an external magnetic field and applied current, the behavior of these Cooper pairs can be described by a single wave function <inline-formula><tex-math id="M3">\begin{document}$ \psi = {\psi _{\rm{0}}}{e^{i\varphi }}$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="1-20201881_M3.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="1-20201881_M3.png"/></alternatives></inline-formula>, and the phase is uniform over the space. When applying an external field but still below a certain threshold, a screening current will be established at the surface, which prohibits the entering of magnetic field, that is so-called Meissner effect. When the external field is larger than this threshold, the magnetic flux will penetrate into the sample, forming the interface of superconducting and normal state regions. According to the sign of this interface energy, we can categorize superconductors into type-I (positive interface energy) and type-II (negative interface energy). Most superconductors found so far are type-II in nature. Due to the negative interface energy in type-II superconductors, the penetrated magnetic flux will separate into the smallest bundle, namely the quantum flux line, with a quantized flux <inline-formula><tex-math id="M4">\begin{document}${\varPhi _0} = h/2e$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="1-20201881_M4.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="1-20201881_M4.png"/></alternatives></inline-formula> (<i>h</i> is the Planck constant and <i>e</i> is the charge of an electron). There are weak repulsive interactions among these vortices, thus usually they will form a lattice, called mixed state. When applying a current, a Lorentz force will exert on the flux lines (vortices) and will make them to move, this will induce energy dissipation and the appreciable feature of zero resistance of a superconductor will be lost. By introducing some defects, impurities or dislocations into the system, it is possible to pin down these vortices and restore the state of zero resistance. The study concerning vortex pinning and dynamics is very important, which helps not only the understanding of fundamental physics, but also to the high power application of type-II superconductors. This paper gives a brief introduction to the vortex dynamics of type-II superconductors.

A Branched Polyelectrolyte Complex Enables Efficient Flame Retardant and Excellent Robustness for Wood/Polymer Composites.

Wood/thermoplastic composites (WPCs) have been restricted in some fields of building construction and electrical equipment because of their inherent high flammability and lower toughness. In this work, a branched crosslinking network polyelectrolyte complex (PEC) has been designed by incorporation of polyethyleneimine (PEI), a cation polyelectrolyte end capped amine groups, into cellulose nanocrystals (CNC), and ammonium polyphosphate (APP) via self-assembling. The hydrogen bonding interactions, penetration, and mechanical interlock provided by PEC effectively enhance the interfacial bonding within matrix, wood fibers, and flame retardant. Interestingly, it generates abundant micropores on the inner structure of WPC. The excellent interfacial bonding performance and easy-to-move molecular chain successfully transfer the stress and induce energy dissipation, simultaneously giving rise to higher strength and toughness for WPC. As well as the PEC endows WPC with a promotion in both smoke suppression and UL-94 V-0 rate. Additionally, the peak heat release rate and total smoke release for WPC obviously reduce by 36.9% and 50.0% respectively in presence of 25% PEC. A simple, eco-friendly, and concise strategy exhibits prospects for fiber-reinforced polymer composites with effective flame retardancy and mechanical robust properties.

Assessment of Cyclic Load Induced Energy Dissipation and Damping on GFRP Composite Laminate

Polymeric composites exhibit load sensitive stiffness unlike the case of homogeneous metallic material. Composites are widely used in dynamic loading environment and hence it is necessary to study their response in terms of structural properties. Behavioural changes of glass epoxy composite laminate on exposure to cyclic loading has been assessed in terms of energy dissipation (Ed) and Damping factor (DF) by hysteresis loop. GFRP composite specimens (UD-0, 0/30/60/0, 0/45/0/-45, 0/90/90/0, and 0/90/0/90) are exposed to low velocity constant amplitude cyclic loading using a laboratory arrangement (by an eccentric disc) at 4.6 Hz and 8.6 Hz frequencies. In fibre-reinforced composites apart from the fibre volume fraction, the fibre interaction angle significantly influences their dynamic properties on loading. Unidirectional (UD-0) laminate exhibits low damping/energy dissipation, while 0/90/0/90 laminate with large fibre interaction angle shows highest damping/energy dissipation. Whereas, symmetric cross ply (0/90/90/0) laminate acts as a performance demarcation among the chosen laminates. Thus, optimum Ed/DF properties of GFRP laminate in dynamic environment is attributed to symmetric lay-up, smaller fibre orientation interaction angle in the lay-up sequence and 0 fibre layer at the boundary.

A Comparative Study of Eddy Viscosity Type Models for Simulating Wave Breaking Induced Energy Dissipation in Boussinesq Models

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Experimental investigation of fatigue crack induced energy dissipation under mixed mode loading

The experimental study of heat flux evolution at the fatigue crack tip during uniaxial and biaxial loading was carried out. The plane samples of Grade 2 titanium alloy were weakened by notch to initiate fatigue crack. A contact heat flux sensor based on the Seebeck effect was used for monitoring of the dissipated energy. During the tests, the samples were subjected to cyclic loading with constant stress amplitudes and different biaxial parameter. Based on the analytical estimation of heat dissipation at the crack tip we proposed an approximation of heat dissipation as a function of crack growth rate. The approximation is universal for all considered loading types (uniaxial and biaxial). A linear correlation between crack growth rate and heat dissipation was obtained.

Gravitational wave GW170817: A new-born sub-millisecond pulsar and the properties of coalescing double neutron stars

The gravitational wave event GW170817 is ascribed to the coalescence of a double neutron star (DNS) based on the multi-messenger observations. Based on the detected gravitational wave frequency by LIGO and the afterglow observations by the optical and Gamma-ray instruments, it is inferred that the outcome of coalescence kilonova of GW170817 is most probably the birth of a fast rotating sub-millisecond pulsar (SMSP), with the spin frequency of ∼ 1490 Hz (period of P ∼ 0.67 ms), and magnetic field of B∼1011−15 G depending on the magnetic reconstruction process of the new NS. The mass and radius of this new born SMSP is estimated to be about ∼ 2.6M⊙ and 12−25 km, respectively, then the EOS and nuclear composition of such a super-spinning and massive compact object is still open, after comparing with the predictions of the known EOS models. The observations of this new type of SMSP after GW170817 is proposed, and its extreme properties are investigated, for instance, its magnetic dipole spin-down induced energy dissipation rate is E˙∼1044(B/1012G)2 erg/s, which is four orders of magnitudes more luminous than that of Crab pulsar, and accordingly its spin-down characteristic age is as short as 30 years. While considering the distance of the source at 130 million light years, the corresponding energy dissipation rate is E˙∼1035(B/1012G)2 erg/s at the location of Crab pulsar, which could be observed by sensitive X, gamma and radio telescopes if this pulsar sweeps its radiation beam across the Earth.

Increase in micro-cracks beneath cleavage fracture surface in carbon steel ESSO specimens

Brittle cracks propagate rapidly, and subsequent brittle fractures in large-scale structures result in associated catastrophic damage. Recent studies have reported the generation of numerous micro-cracks during brittle crack propagation of low-carbon steel used in shipbuilding. As micro cracking induces energy dissipation by generating a new surface, it may thus affect crack propagation properties. However, the mechanism of micro cracking during rapid crack propagation is not yet properly understood. In this study, micro-cracks generated during rapid crack propagation were investigated for certain ESSO carbon steel specimens. Three types of carbon steel were used: high-carbon steel, low-carbon steel, and ultra-low-carbon steel. Numerous micro-cracks were observed underneath the main fracture surface, and their numbers increased with extension of the primary brittle crack. The total micro-crack lengths were evaluated with the stress intensity factor during crack propagation: a high stress intensity factor caused numerous micro-cracking over a large area, and the relationship between the stress intensity factor and total length of micro-cracks was similar, regardless of the amount of carbon in the steel. Furthermore, the influence of micro cracking on dissipation energy was analyzed using the Charpy impact test. A quenching treatment for low-carbon steel was applied to generate many martensite–austenite (M–A) constituents that induced numerous micro-cracks. Numerous micro-cracks were detected beneath the full cleavage fracture surface of the Charpy specimen with quenching treatment, and the Charpy absorbed energy was increased at −196 °C. This increase in micro-cracks might cause energy dissipation by generating a new surface during brittle crack propagation.

Effect of Ethylene/butyl methacrylate/Glycidyl Methacrylate Terpolymer on toughness and biodegradation of poly (l-lactic acid).

The super toughed poly(l-lactic acid) (PLLA) blends with various content of Ethylene/butyl methacrylate/Glycidyl Methacrylate Terpolymer (GEBMA) were prepared by melt compounding. The blend was an immiscible system but had good compatibility due to the chemical reaction between the epoxy groups of GEBMA and the end group of PLLA during the blending process. The addition of GEBMA suppressed the cold crystallization and non-isothermal melt crystallization of PLLA. GEBMA was a very effective toughening agent for PLLA. The addition of only 15 wt% GEBMA, the elongation at break and impact strength of the blend were significantly improved compared to neat PLLA, which were 63 and 18 times that of neat PLLA, respectively. Scanning electron microscopy (SEM) images of the impact fracture surfaces of the blends showed a large amount of cavities and plastic deformation in the blend, which induced energy dissipation and therefore led to the improvement in toughness of the PLLA/GEBMA blends. For the PLLA/GEBMA blown films, the addition of GEBMA significantly improved the flexibility of PLLA/GEBMA blown film. The tear strength reached a maximum of 143.5 kN/m in the machine direction (MD) and 166.7 kN/m in the transverse direction (TD). Moreover, the biodegradation of PLLA was enhanced after blends preparation.