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This paper addresses the problem of scheduling $ n $ equal-processing-time jobs with release dates non-preemptively on identical machines to optimize two criteria simultaneously or hierarchically. For simultaneous optimization of total completion time (and makespan) and maximum cost, an algorithm is presented which can produce all Pareto-optimal points together with the corresponding schedules. The algorithm is then adapted to solve the hierarchical optimization of two min-max criteria, and the final schedule has a minimum total completion time and minimum makespan among the hierarchical optimal schedules. The two algorithms provided in this paper run in $ O(n^3) $ time.

This paper proposes a primary-side linear control strategy to realize the constant current (CC)/voltage (CV) charging for the wireless power transfer (WPT) system, based on the LCC-N circuit. Different from the conventional compensation topology used in control strategies, this paper combines magnetic integration structure on the primary side and non-compensation topology on the secondary side. Firstly, the LCC-N magnetic integration and non-compensation topology is introduced. An improved parameters identification method considering the non-pure resistive input impedance characteristics of the rectifier is proposed to identify the current, voltage and equivalent resistance of the load, based on the LCC-N topology. In the process of identification, the relationship between the input impedance of the rectifier and the load is needless. Then, according to the LCC-N output characteristics and identified load parameters, the relationship between the input voltage and load current and voltage is simplified to linear through the linear superposition of fundamental wave and third harmonic. A linear control strategy on the primary side is proposed to achieve CC/CV output. Finally, a 1 kW WPT prototype is built. The experimental results show that the maximum error of the output current and voltage are 1.8% and 1.2% during the CC and CV charging, respectively.

The immobilization of homogeneous catalysts has always been a hot issue in the field of catalysis. In this paper, in an attempt to immobilize the homogeneous [Ni(Me6Tren)X]X (X = I, Br, Cl)-type catalyst with porous organic polymer (POP), the heterogeneous catalyst PBTP-Me6Tren(Ni) (POP-Ni) was designed and constructed by quaternization of the porous bromomethyl benzene polymer (PBTP) with tri[2-(dimethylamino)ethyl]amine (Me6Tren) followed by coordination of the Ni(II) Lewis acidic center. Evaluation of the performance of the POP-Ni catalyst found it was able to catalyze the CO2 cycloaddition with epichlorohydrin in N,N-dimethylformamide (DMF), affording 97.5% yield with 99% selectivity of chloropropylene carbonate under ambient conditions (80 °C, CO2 balloon). The excellent catalytic performance of POP-Ni could be attributed to its porous properties, the intramolecular synergy between Lewis acid Ni(II) and nucleophilic Br anion, and the efficient adsorption of CO2 by the multiamines Me6Tren. In addition, POP-Ni can be conveniently recovered through simple centrifugation, and up to 91.8% yield can be obtained on the sixth run. This research provided a facile approach to multifunctional POP-supported Ni(II) catalysts and may find promising application for sustainable and green synthesis of cyclic carbonates.

Metal-organic frameworks (MOFs) provide opportunities for the design of high-efficiency catalysts attributed to their high compositional and structural tunability. Meanwhile, the huge number of MOFs poses a great challenge to experimental-intensive development of high-performance functional applications. By taking the computationally feasible and structurally representative trigonal prismatic secondary building units (SBUs) of MOFs as the entry point, we introduce a descriptor-based approach for designing high-performance MOFs for the oxygen evolution reaction (OER). The electrostatic potential-derived charge (ESPC) is identified as a robust and universal OER performance descriptor of MOFs, showing a distinct linear relationship with the onset potentials of OER elemental steps. Importantly, we establish an ESPC-based physical pattern of active site-intermediate binding strength, which interprets the rationality of ESPC as an OER performance descriptor. We further reveal that the SBUs with Ni/Cu as active site atoms while Mn/Fe/Co/Ni as spectator atoms have excellent OER activity through the variation pattern of ESPC along with metal composition. The universal correlation between ESPC and OER activity provides a rational rule for designing high-performance MOF-based OER electrocatalysts and can be easily extended to design functional MOFs for a rich variety of catalytic applications.

Epoxy resins are currently the most widely used thermosetting polymers due to their high thermal stability, excellent electrical insulation, and chemical resistance.

This paper proposes an receiver position identification (RPI) method based on magnetic integration compensation inductance, using the voltage and current of the magnetic integration compensation inductance, and the transmitter current. Compared with the conventional methods, the proposed method does not add additional detection coils and position sensors, and RPI is realized based on electric parameters of the primary magnetic integration compensation inductance and transmitter. Firstly, the coupling relationships between the magnetic integration compensation inductance, transmitter and receiver with different wiring modes are analyzed. Meanwhile, an integration compensation inductance structure with minimal coupling impact on the receiver and transmitter coils is determined. Then, based on the magnetic integration compensation inductance structure, the RPI method is analyzed, which can detect the receiver position in the x-y plane without secondary-side information. Finally, the proposed RPI method is experimentally verified, and the results show that the proposed method can effectively identify the receiver position.

Dynamic wireless power transfer(DWPT) technology is gradually making the prospect of charging on road of EVs possible. However, DWPT system should be optimized in many aspects before it can really be utilized on road. For example, the control of energy transfer for a DWPT system is much complicated than a static wireless power transfer system since the coupling of transceiving coils changes with the moving of the EV. In this paper, an energy transfer control method based on the estimation of the load and mutual inductance of the segmented DWPT system is proposed. The relation between the load and the reflected impedance of the primary side is studied, and the parameters of the secondary-side LCC network are tuned to avoid the two-solution problems in the estimation of the load. Based on the results of estimation, a two-cases controlling strategy is proposed to switch between power-on station and detection station of the DWPT system according the target of energy transferring. A 800-W prototype of 4-transmitting-coil dynamic wireless power transfer system is built and experiments show that the proposed energy-transfer control is proved to be efficient to regulate the energy and achieve fast response characteristics. Compared with the traditional controlling methods which usually aim to achieve maximum energy transfer, the method in this paper can control the transferred energy according to the target value of energy, making the control more flexible without the use of communication.

Due to the advantages of high convergence accuracy, fast training speed, and good generalization performance, the extreme learning machine is widely used in model identification. However, a gas turbine is a complex nonlinear system, and its sampling data are often time-sensitive and have measurement noise. This article proposes an online sequential regularization extreme learning machine algorithm based on the forgetting factor (FOS_RELM) to improve gas turbine identification performance. The proposed FOS_RELM not only retains the advantages of the extreme learning machine algorithm but also enhances the learning effect by rapidly discarding obsolete data during the learning process and improves the anti-interference performance by using the regularization principle. A detailed performance comparison of the FOS_RELM with the extreme learning machine algorithm and regularized extreme learning machine algorithm is carried out in the model identification of a gas turbine. The results show that the FOS_RELM has higher accuracy and better robustness than the extreme learning machine algorithm and regularized extreme learning machine algorithm. All in all, the proposed algorithm provides a candidate technique for modeling actual gas turbine units.

The lithium-sulfur (Li-S) battery is one of the most promising substitutes for current energy storage systems because of its low cost, high theoretical capacity, and high energy density. However, the high solubility of intermediate products (i.e., lithium polysulfides) and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency, which hinder the practical application of Li-S batteries. In this study, block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S batteries. Electrochemical performance improvements are attributed to the synergistic effects contributed by the different units of the block copolymer. The ethylene oxide unit traps polysulfide, which bonds strongly with the intermediate lithium polysulfide, and enhances the transport of lithium ions to reach high capacity. Meanwhile, the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume changes. By enabling multiple functions via different units in the polymer chain, high sulfur utilization is achieved, polysulfide diffusion is confined, and the shuttle effect is suppressed during the cycle life of Li-S batteries, as revealed by operando ultraviolet–visible spectroscopy and S K-edge X-ray absorption spectroscopy.

The problem of minimizing makespan (maximum completion time) on uniform machines with restricted assignment is considered. The machines differ in their speeds and functionalities. Each job has a set of machines to which it can be assigned, called its processing set. The goal is to finish the jobs as soon as possible. There exist 4/3-approximation algorithms for the cases of inclusive and tree-hierarchical assignment restrictions, under an assumption that machines with higher capabilities also run at higher speeds. We eliminate the assumption and present algorithms with approximation ratios 2 and 4/3 for both cases.

This paper studies the Pareto scheduling problem of minimizing total weighted completion time and maximum cost on a single machine. It is known that the problem is strongly NP-hard. Algorithms with running time $ O(n^3) $ are presented for the following cases: arbitrary processing times, equal release dates and equal weights; equal processing times, arbitrary release dates and equal weights; equal processing times, equal release dates and arbitrary weights.

This paper presents a multi-objective design method of underwater wireless power transfer (UWPT) system for autonomous underwater vehicles (AUV) based on the cooperative design of compensation network and a DC/DC converter, considering seawater eddy current loss. Firstly, the electromagnetic field model of the underwater coil is established based on the non-axisymmetric model, and the analysis method of eddy current loss is given. Then, according to the circuit model with seawater eddy current loss, a two-port network including a compensation network and coil coupling model, is established. The cooperative design method of compensation network and DC/DC converter is presented to improve the efficiency of the UWPT system and reduce the electrical stress of the inverter, considering seawater eddy current loss. Finally, a 1 kW AUV UWPT system prototype is built. The experimental results prove that the proposed seawater eddy current loss analysis method is effective. The experimental results also show that the proposed compensation network and DC / DC converter duty cycle design method can achieve the purpose of constant voltage output, optimization of system efficiency, reduction of inverter electrical stress and inverter zero-voltage-switch.

In this study, a series of gelators (Gn, n is the number of carbon atoms of used fatty alcohol, n = 2, 4, 6, 8, 10, 12, 14, 16 and 18) were synthesized by reacting 4,4′-diphenylmethane diisocyanate with fatty alcohols. Meanwhile, n-octadecane-based gels as form-stable phase change materials (FSPCMs) for thermal energy storage were prepared by introducing Gn into n-octadecane. The gel properties were confirmed by “tube testing method.” The results show that Gn (n = 2, 4) were immiscible with n-octadecane, while a lower mass percentage content (≤ 6 mass%) of Gn (n = 6, 8, 10, 12, 14, 16, 18) can gelate the n-octadecane and the gel-to-sol transition temperature is higher than 100 °C. The chemical structures, morphologies and crystalline properties of prepared FSPCMs were determined by Fourier transform infrared spectroscopy, scanning electron microscope, X-ray diffraction and polarized optical microscope. It is found that Gn could self-assemble into lamellar three-dimensional network structure to restrict the leakage of melted n-octadecane. Differential scanning calorimetry analysis results indicate that prepared FSPCMs exhibit high latent heats and latent heat efficiency is greatly higher than that of other traditional FSPCMs. Moreover, thermal cycling test results confirm that the prepared FSPCMs have good thermal reliability and reusability. This study is attractive for preparation of FSPCMs with high latent heats. Prepared FSPCMs could be potentially applied in the field of thermal energy storage for thermal comfort.

Crosslinked polyurethane with excellent mechanical property, solvent resistance, and transparency has become one of the most widely used materials. However, the presence of chemical crosslinks makes it difficult to be reprocessed once molded, which largely restricts its recycling and reusing, resulting in the serious waste problems. Therefore, it is of great significance to prepare a new type of crosslinked polyurethane with reprocessing function. In this work, a novel reprocessable polyurethane (DOPU) based on reversible dibutanone oxime-carbamate bonds is facilely prepared. The gel fraction of DOPUs is all higher than 95%, endowing it with excellent solvent resistance. Meanwhile, the visible light transmittance of DOPUs can reach up to 97.48%. After four thermal recycles, the tensile strength and elongation at break of recycled DOPUs can still remain at 3.21 MPa and 219.09%, respectively. Importantly, the synthesized DOPUs exhibit excellent elastic shape memory and permanent shape reconstruction properties under thermal stimulation. The dibutanone oxime-carbamate bonds can also be degraded under UV irradiation, making this material easily degradable. Hence, this material has potential applications in coatings, elastomers, and some other fields.

High energy density lithium-ion batteries with preferable cycling stability are critical for the development of all-electric vehicles. Silicon (Si) has demonstrated a remarkable potential for application as anode materials due to its superior capacity performance and worldwide abundance. However, Si intrinsically undergoes substantial volume fluctuation during repeated lithiation/delithiation processes, which pulverizes the Si particles and undermines the integrity of the electrode structures, thus resulting in frustrating cycling stability. We developed a polymer binder with a highly stretchable and elastic network structure that can accommodate volume variation of Si. This was realized by an in situ cross-linking of polyacrylic acid (PAA) with isocyanate-terminated polyurethane oligomers that consist of polyethylene glycol (PEG) chains and 2-ureido-4-pyrimidinone (UPy) moieties through the reaction between isocyanate and carboxyl during the electrode preparation process. In this binder network, PAA could strongly adhere to the Si particles by forming hydrogen bonding with the surface hydroxyl groups. The PEG chains induce the flexibility of the polymer network, while the UPy moieties endow the polymer network with desirable mechanical strength through the formation of reversible and strong quadruple H-bonding cross-linkers. This binder not only can sufficiently accommodate the volume change of Si but can also provide a strong mechanical support to effectively sustain the integrity for the Si anode, consequently enhancing cycle stability and rate performance.

Background The prognostic value of serum bilirubin in stroke is controversial, since bilirubin has both neuroprotective and neurotoxic properties. We aimed to investigate the association between serum bilirubin, including total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) and poor functional outcomes in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA). Methods All patients with AIS or TIA were recruited from the Third China National Stroke Registry. The poor functional outcomes included modified Rankin Scale (mRS) score 2–6 and 3–6 at 3 months and 1 year. Multivariable logistic regression was used to investigate the associations of TBIL, DBIL, and IBIL with poor functional outcomes. Results Among 11,121 enrolled patients, the median (interquartile range) of TBIL, DBIL, and IBIL was 13.30 (9.90–17.70), 3.80 (2.70–5.30), and 9.30 (6.70–12.80) µmol/L. After adjustment for conventional confounding factors, patients in the highest TBIL quartile had the highest proportion of mRS score 2–6 at 3 months (odds ratio [OR], 1.37; 95 % confidence interval [CI], 1.19–1.59) and 1 year (OR, 1.31; 95 % CI, 1.13–1.52), and mRS score 3–6 at 3 months (OR, 1.33; 95 % CI, 1.11–1.59) and 1 year (OR, 1.28; 95 % CI, 1.07–1.53), when compared to patients in the lowest TBIL quartile. Similar results were observed for DBIL and IBIL. We also found J-shaped associations between serum bilirubin levels and each outcome. Conclusions Elevated levels of serum bilirubin were significantly associated with poor functional outcomes in patients with AIS or TIA at 3 months and 1 year.

This paper presents a research on the characteristics of wireless power transfer (WPT) system based on LCC/N magnetic integration compensation circuit. Compared with the traditional compensation circuits, the LCC/N compensation circuit has no compensation circuit on the secondary side and integrates the compensation inductor on the primary side into the transmitter. First, the two-port network considering the coupling relationship between magnetic integration compensation inductance and receiver coil is established. Then, based on the two-port network, the output impedance angle of the inverter, transmission power and efficiency of the WPT system employing LCC/N compensation circuit is analyzed under variations of coupling coefficient and load. Finally, the analysis of the characteristics of the WPT system based on the LCC/N magnetic integration compensation circuit is verified by simulations and experiments. And the results show that the analysis of characteristics is effective.

Traditional thermosetting polyureas (TPUs) with eminently comprehensive performance have been used in a variety of industrial applications. However, they suffer from a certain intractable difficult...

Intrinsic cross-linked waterborne polyurethane (CWPU) was successfully synthesized for the first time through solvent-free condensation polymerization, in which green castor oil (CO) was used as the cross-linking agent. The totally solvent-free process was realized by using hydrophilic polypropylene glycol as hydrophilic segment, which was synthesized by the esterification of polypropylene glycol with pyromellitic dianhydride. The effect of CO content in the soft segment of the prepared CWPU on emulsion properties was investigated by laser particle size distribution test, and the prepared CWPU emulsion showed uniform size distribution (0.117–0.275 µm) and milky white appearance after storing at ambient temperature for 6 month. Additionally, the effect of CO content in CWPU films on static mechanical properties, dynamic mechanical properties, hydrophilicity and thermal stability was also studied by tensile test, dynamic mechanical analysis, water absorption and contact angle measurement as well as thermogravimetric analysis. The prepared cross-linked CWPU films have good stability and outstanding mechanical strength (11.94–34.51 MPa), making them adequate supplement for the conventional waterborne polyurethanes.

A facile strategy of incorporating dynamic carboxylic zinc ion interactions into traditional linear polymers was developed to achieve the recyclability of crosslinked polymers. For newly synthesized polymers, pendant carboxyl can be incorporated into polymer chains during the synthesis process and subsequently crosslinked with zinc acetate. For commercial thermoplastics with only C–C bonds in the backbone, reactive processing offers an alternative approach to prepare vitrimers. This strategy is expected to be an effective approach for high performance recyclable polymer systems.

Conventional solid–solid phase-change materials (SSPCMs) exhibit good thermal energy storage (TES) ability and shape stability, but they cannot be recycled and re-shaped once fabricated due to the chemical cross-links. Hence, endowing SSPCMs with recyclability and malleable properties is advantageous for numerous applications, and contributes to environmental protection. Herein, a novel class of dynamic cross-linked SSPCMs (DC-PCMs) was facilely fabricated by bonding polyethylene glycol (PEG) to a polymeric skeleton through the thermally reversible Diels–Alder (DA) reaction for sustainable TES. PEG segments function as energy-storage units, while the polymeric skeleton affords shape stability and robust mechanical properties. The crystalline structure of DC-PCMs was investigated by X-ray diffraction (XRD), polarized optical microscopy (POM) and differential scanning calorimetry (DSC). DSC characterization also confirms the reversible energy-capture and release ability of DC-PCMs. The results suggest that SSPCMs show typical solid–solid phase transitions within the temperature range from 40 °C to 70 °C and can achieve a high latent heat storage capacity of about 107.2 J g−1. Meanwhile, the thermally reversible DA reaction endows the DC-PCMs with good thermal recyclability and solid-state plasticity. After multiple thermal cycles, DC-PCMs can retain the original mechanical properties and TES ability. Moreover, the DC-PCMs are highly scalable for practical applications because of their uncomplicated and cost-effective fabrication.

Acrylic latex laminating adhesives (ALLAs) were successfully prepared via a monomer-starved seeded semi-continuous emulsion polymerization with butyl acrylate (BA), methyl methacrylate (MMA), styrene (St), acrylamide (Am), and methacrylate glycidyl ether (GMA) as monomers. Impacts of GMA on the final latex, the dried latex films and the adhesive properties of ALLAs were investigated, respectively. The results indicated that the increase of GMA contents in the pre-emulsion feed has no apparent effect on the final latex average particle size and size distribution, while the gel contents, glass transition temperature (Tg) and water contact angle of the ALLAs gradually increased, and the molecular weight (Mn, Mw) obviously increased. Additionally, as the amount of GMA increased from 0 to 10 wt%, the maximum peel strength of the composite films reached 3.72 N/15mm with 5 wt% GMA contents. When heated to 65 °C, the peel strength of the composite films with 5 wt% of GMA can still maintain an acceptable ...

In this work, we proposed an efficient redox initiating system (ROIS) for free radical polymerization of acrylate-functionalized polyurethanes (APUAs) at room temperature. In this ROIS, cumene hydroperoxide and aliphatic tetraethylenepentamine were used as the oxidizing agent and reducing agent, respectively. Fourier transform infrared spectroscopy results of APUAs and cured polymers show that this ROIS can enable both surface and inner curing of APUAs. The oxygen inhibition can be overcome by the reaction of tetraethylenepentamine with the hydroperoxide produced during the curing process in air atmosphere. The obtained polymer films show good transmittance, high crosslinking density (>86%), good thermal stability and suitable tensile strength (7.64 MPa), which can be applied in coating and adhesive industries. In addition, redox polymerization kinetic was studied by using differential scanning calorimetry.

This article presents an approximate linearization method for the rectifier load used in wireless power transfer (WPT) systems. The related complex non-linear relationship between the WPT load and rectifier input impedance is transferred to simple linear expressions through the proposed method, which will be helpful for system design and control. First, the equivalent circuit model is established considering WPT system with the uncontrolled diode rectifier and LCC compensation. Then, the complete expressions of the rectifier load equivalent impedance are obtained based on the model. Moreover, the monotonicity of the parameter relationships is discussed in order to clarify the linearization prerequisite. Furthermore, the linearization process is presented and the analysis indicates that it will be affected by the selected linearized point and the related WPT parameters. Finally, a WPT prototype is developed. The experiments and simulations have proved the effectiveness of the presented rectifier load analysis and its linearization method on the conditions of mutual-inductance, compensation parameter, and battery voltage variations.

This paper presents an eddy current loss analysis method in underwater wireless power transfer (UWPT). Firstly, this paper uses analytical solution method to analyze the eddy current loss in the seawater. Also, the influence of the current and working frequency on the eddy current loss is discussed to analyze the eddy current loss. Then, based the eddy current loss analysis and coil mutual inductance model, a coil mutual inductance model with the eddy current loss is built. Finally, a 1kW underwater WPT prototype is developed. Finite element simulation and experimental results have proved that the analysis of the eddy current loss and the coils mutual inductance model with the eddy current loss is effective.

Author(s): Fang, C; Liu, Z; Lau, J; Elzouka, M; Zhang, G; Khomein, P; Lubner, S; Ross, PN; Liu, G | Abstract: The solid electrolyte interphase (SEI) formed during the cycling of lithium-ion batteries (LIBs) by decomposition of electrolyte molecules has key impact on device performance. However, the detailed decomposition process and distribution of products remain a mystery due to the wide variety of electrochemical pathways and the lack of facile analytical methods for chemical characterization of SEIs. In this report, a gradient polarity solvent wash technique involving the use of solvents with gradually increased polarities is employed to sequentially remove different SEI components from electrode surfaces. Fourier transform infrared (FTIR) spectroscopy is utilized to characterize the SEI composition. The impacts of electrolyte additives and discharge rates over SEI formation are illustrated. This study presents a new concept of rationally controlled solvent wash technique for electrode surface analysis that can selectively remove targeted components. The findings in this study provide experimental support for the slow charge formation processes commonly employed for LIBs in industry.

The Li-S battery is a promising next-generation technology due to its high theoretical energy density (2600 Wh kg−1) and low active material cost. However, poor cycling stability and coulombic efficiency caused by polysulfide dissolution have proven to be major obstacles for a practical Li-S battery implementation. In this work, we develop a novel strategy to suppress polysulfide dissolution using hydrofluoroethers (HFEs) with bi-functional, amphiphlic surfactant-like design: a polar lithiophilic “head” attached to a fluorinated lithiophobic “tail.” A unique solvation mechanism is proposed for these solvents whereby dissociated lithium ions are readily coordinated with lithiophilic “head” to induce self-assembly into micelle-like complex structures. Complex formation is verified experimentally by changing the additive structure and concentration using small angle X-ray scattering (SAXS). These HFE-based electrolytes are found to prevent polysulfide dissolution and to have excellent chemical compatibility with lithium metal: Li||Cu stripping/plating tests reveal high coulombic efficiency (>99.5%), modest polarization, and smooth surface morphology of the uniformly deposited lithium. Li-S cells are demonstrated with 1395 mAh g−1 initial capacity and 71.9% retention over 100 cycles at >99.5% efficiency—evidence that the micelle structure of the amphiphilic additives in HFEs can prohibit polysulfide dissolution while enabling facile Li+ transport and anode passivation.

Wireless power transfer (WPT) system has gathered attention for years with its safety, convenience and flexibility. Control of the whole system has always been a key issue for WPT technology. A lot of methods of parameter estimation have been presented in relevant literature, providing accordance for controlling. In this paper, an online parameter estimation method for WPT system is proposed based on the measurement of input voltage and current of the inverter. A DC input side model for the inverter was built, and the equivalent load of the inverter can be determined by the input voltage and current. Then, by studying the characteristics of the tangent of the reflected angle, a curve fitting method was proposed to estimate the system load. The mutual inductance of coils was also estimated to provide information of the system. The experiments results showed that the proposed method can reduce the estimating error of the load to 7%.

A carboxy modified long-chain diol (CMLCD) was synthesized for the first time through esterification of pyromellitic dianhydride (PMDA) and polytetramethylene glycol 1000 (PTMG1000). Waterborne polyurethane (WPU) was prepared based on an organic solvent-free and self-catalytic process, using synthesized CMLCD as a hydrophilic diol. The CMLCD has self-catalytic ability to the reaction of hydroxyl and isocyanate during the prepolymerization, which can greatly shorten the preparation period and avoid the utilization of highly toxic catalyst such as dibutyltin dilaurate. Importantly, the prepared WPU has narrow particle size distribution with the average particle size of 137 nm, which leads to good stability even centrifugated at 3000 rpm. Mechanical test results show that the WPU film possesses good mechanical performance with the tensile strength of 59.3 MPa and elongation at break of 819.2%. Additionally, the prepared WPU film has high water resistance. This study is attractive for future green WPU in industrial production and application.