Polysiloxane has found extensive applications in advanced composite materials. However, the low compatibility with most polymers always resulted in the formation of macroscopic phase separation and thus limited its functional utilization to a maximum extent. Self-assembly of block copolymers has been developed as an efficient technique for preparing nanomaterials by selectively allocating each block at the core or shell region, thus facilitating multiple applications. However, the scalable fabrication and functional application of nano-objects with a soft polysiloxane core remain challenging, despite being boosted with theoretical significance and urgent applications. To this aim, herein, the poly(methyl methacrylate)-b-poly(dimethylsiloxane-co-vinylmethylsiloxane)-b-poly(methyl methacrylate) (PMMA-b-P(DMS-co-VMS)-b-PMMA, MSM) triblock copolymers were first designed and synthesized. Subsequently, employing a heat-induced self-assembly (HISA) process, the nano-objects with regular morphologies and controlled sizes were prepared in selective solvents and further stabilized by in situ cross-linking of the P(DMS-co-VMS) core. The observed low melting temperature (T m) of the P(DMS-co-VMS) core confirmed that the soft polysiloxane core was successfully fabricated. The nano-objects with regular morphologies, controlled sizes, adjustable cross-linking densities, tunable PMMA contents, and block lengths significantly enhanced the toughening behavior and flame-retardant performance of PMMA-based composites, which were obviously superior to the counterpart of MSM triblock copolymer with undefined microphase. The HISA has proven to be an efficient technique for fabricating nano-objects with a soft polysiloxane core, which demonstrates significant potential as functional additives in practical applications.

The fabrication of nanostructures is an urgent yet challenging process due to the complicated parameters involved in the self-assembly process. Uniquely, acting as the most efficient strategy, the self-assembly behavior of multiblock copolymers can be significantly modulated by varying the block sequence parameter. In this study, polyisoprene (PI), polystyrene (PS), and crystalline pi-conjugated poly(3-hexylthiophene) (P3HT) were elaborately combined into PI-b-PS-b-P3HT, PS-b-PI-b-P3HT, and PS-b-P3HT-b-PI triblock terpolymers with different block sequences via controlled synthetic methods. The self-assembly of triblock terpolymers was comprehensively investigated and compared using n-heptane/ethyl acetate (Hep/EA) and N,N-dimethylacetamide/ethyl acetate (DMAc/EA) as selective cosolvents. Under the same cosolvents and degree of polymerization (DP) of the blocks, the block sequences were found to significantly influence the morphological formation of nano-objects due to variations in the crystallization ability of the P3HT block and selective solvation or plasticization of the PI or PS blocks. Furthermore, to provide a comprehensive understanding of the self-assembly and depict a full morphology diagram, the self-assembly behavior of triblock terpolymers with different block sequences was compared by varying the block compositions of the triblock terpolymers. This work provides fundamental insights into the self-assembly mechanism of rod-coil multiblock copolymers and has implications for designing functional nanomaterials.

Twelve novel thiazole Schiff base derivatives (5a-5l) were successfully synthesized and confirmed using Nuclear magnetic resonance (H-1 NMR and C-13 NMR), Fourier transform infrared spectroscopy (FT-IR), and elemental analysis. The antioxidant activities of compounds 5a-5l were evaluated via DPPH radical scavenging assay, revealing that compounds 5c (IC50 = 18.71 +/- 2.02 mu g/mL), 5d (IC50 = 21.07 +/- 2.21), and 5i (IC50 = 21.66 +/- 3.12) exhibited significant antioxidant potency. The halogen substituents (fluoro-, chloro-, bromo-) on the phenyl ring significantly influenced antioxidant performance (F > Cl > Br). Density functional theory (DFT) calculations were employed for geometric optimization, followed by natural bond orbital (NBO), frontier molecular orbital (FMO), and molecular electrostatic potential (MEP) analyses. The most credible transition observed in compound 5c was pi (C2-C3) -> pi*(C4-C5), with highest stabilization energy of 22.75 kcal/mol. Molecular docking studies indicated binding energies ranging from-5.41 to-6.87 kcal/mol for compounds 5a-5l, with compound 5c showing the strongest binding energy (-6.87 kcal/mol), confirming robust interactions. All target compounds complied with Lipinski's Rule of Five, while 5c and 5d exhibited superior drug-likeness. This work provides a theoretical foundation for designing novel thiazole Schiff base derivatives and offers critical insights for structural optimization of high-efficiency antioxidants.

Electrochemical benzylic C(sp3)-H/N-H cross-coupling represents a green, sustainable, and straightforward strategy to construct benzylic C(sp3)-N bonds. Herein, a direct electrochemical intermolecular benzylic C(sp3)-H imidation of diarylmethanes and alkylarenes with N-acylsulfonamides or sulfonimides is described, which proceeds in an undivided cell under transition-metal- and external-oxidant-free conditions. This methodology does not require prefunctionalized reagents and utilizes readily available and cost-effective sodium bromide as both a mediator and a supporting electrolyte. The cross-coupling strategy shows good tolerance to a diverse array of diarylmethanes, alkylarenes, N-acylsulfonamides, and sulfonimides, enabling selective benzylic C-H imidation of both primary and secondary benzylic C(sp3)-H bonds. The synthetic potential of this approach has been substantiated through successful scale-up reactions, product derivatizations, and late-stage functionalization of bioactive molecules and pharmaceuticals. Based on comprehensive mechanistic experiments and cyclic voltammetry studies, a mechanism involving bromine-mediated formation of an N-bromo-imidyl species is proposed. The N-bromo species is supposed to undergo N-Br bond homolysis to generate a nitrogen-centered imidyl radical, which would facilitate intermolecular benzylic C(sp3)-H imidation through a hydrogen atom transfer pathway.

Nine novel thiazole Schiff base derivatives (5a-5i) containing various aromatic heterocycles were synthesized through a three-step procedure from halogenated acetophenones and heterocyclic aldehydes. And their structures were confirmed using 1H NMR, 13C NMR, FT-IR spectroscopy, and elemental analysis. DPPH radical scavenging assay indicated compound 5g demonstrated the strongest antioxidant activity (IC50 = 26.71 +/- 3.02 mu M). The in vitro antibacterial activity evaluation indicated compound 5h exhibited the best antibacterial activities, with inhibition zone diameter of 9.77 +/- 0.42 mm against Escherichia coli and 9.63 +/- 0.15 mm against Staphylococcus aureus. DFT calculations (NBO, FMO, and MEP analysis) of compounds (5a-5i) were performed to elucidate the binding mechanisms of the antioxidant/antibacterial activities and biomacromolecules from the perspective of electronic structure. Molecular docking studies showed that compounds (5a-5i) exhibited strong binding characteristics with 1KZN (-6.53 to-8.17 kcal/mol), 2BV6 (-5.13 to-6.11 kcal/mol), and 3MNG (-6.05 to-7.10 kcal/mol), which were consistent with the experimental trends of antioxidant and antibacterial activities. ADMET predictions indicate that all target compounds comply with Lipinski's rule of five and exhibit good potential for oral bioavailability. However, some compounds show high lipophilicity and potential tumorigenic risk, necessitating further structural optimization to enhance safety. This study provides a theoretical basis and structural references for the design and development of novel antibacterial and antioxidant agents based on the thiazole Schiff base.

Inspired by the platform-molecule concept central to modern biorefineries, we propose a polymer-editing approach based on backbone and side-chain modifications that activate inherent functional motifs in commodity plastics, enabling programmable cascade transformations to convert polymeric scaffolds into tailored small molecules, functional oligomers, and advanced materials. Using hydrogenated poly(ethylene terephthalate) (PECHD) as a paradigmatic "backbone-preedited" synthon, we efficiently transform waste PET into trans-enriched 1,4-cyclohexanedicarboxylic acid (CHDA), its mono- and diesters, and cycloaliphatic oligodiols that act as tunable precursors for degradable polyurethane elastomers. Mechanistic and kinetic studies indicate that the semi-rigid alicyclic backbone and ester linkages of PECHD promote specific reaction pathways, resulting in lower energy barriers for selective ester cleavage and facilitating efficient diverse hydrogenation-depolymerization cascades. Additionally, through side-chain editing, polystyrene (PS) is converted-via its hydrogenated intermediates-into cyclohexanone and polyethylene-like polyketones through tandem hydrogenation-oxidation. Collectively, this work establishes a flexible molecular editing strategy that enables stereoselective and catalytically programmable refunctionalization of polymer architectures, providing versatile, scalable, and sustainable design principles for a circular plastic economy.

Block copolymers (BCPs) are well-documented to undergo self-assembly into diverse nanostructures. Uniquely, BCPs with crystallizable core-forming blocks undergo crystallization-driven self-assembly (CDSA), typically yielding one-dimensional (1D) nanowires and two-dimensional (2D) nanosheets. However, the precise control over morphologies, sizes, and aspect ratios of 2D nanosheets remains challenging. Herein, we present a one-pot "heating-cooling-aging" CDSA strategy for polyethylene-block-poly(4-tert-butoxystyrene) (PE-b-PtBOS) BCPs, which is implemented in a selective solvent of toluene over a broad concentration range of 0.025 similar to 5.0 wt %. This strategy enables the fabrication of uniform hexagonal/rhombic nanosheets with precisely tunable sizes and aspect ratios by manipulating key parameters of the annealing temperature, the degree of polymerization for PtBOS (DPPtBOS), and concentration. Specifically, at lower DPPtBOS, spontaneous nucleation and growth enable the rapid fabrication of molecularly thin, uniform, and tunable nanosheets, whereas at higher DPPtBOS, the formation kinetics of such nanosheets slows down significantly. The nanosheet size is facilely tailorable by adjusting the annealing temperature, as this parameter directly modulates the number of crystal nuclei, while the aspect ratios of these hexagonal/rhombic nanosheets can be readily regulated by varying the concentration or DPPtBOS. Uniquely, a deliberate bidirectional morphological transition between hexagonal and rhombic nanosheets can also be achieved by modulating the DPPtBOS, concentration, and cooling rate. This work provides new insights into how experimental parameters influence the CDSA process and provides an efficient, versatile route for the controlled synthesis of 2D nanosheets.

ABA triblock copolymers are among the most commercially available thermoplastic elastomers (TPEs). However, their self-assembly characteristics restrict the tunability of properties (such as strength and toughness). Blending has long been employed for performance regulation, yet the lack of a clear mechanism has limited its effectiveness. A series of previous studies have demonstrated that the presence of long and short chains can amplify the spontaneous curvature, thereby stabilizing discrete phases such as spheres or cylinders at a large volume fraction. In this work, we first employed dissipative particle dynamics (DPD) to investigate the self-assembly behavior of ABA/ABA blends and identified discrete phases at large f A. Our DPD results demonstrate that blending ABA copolymers with equal middle blocks can broaden the regions of discrete phases by amplifying the spontaneous curvature toward the A-block, whereas blending with unequal middle blocks exerts additional influences on the mechanical properties. Guided by DPD results, we synthesized a number of polystyrene-block-polyisoprene-block-polystyrene (SIS) triblock copolymer samples. We prepared the blending samples and examined their self-assembly morphologies by using small-angle X-ray scattering, verifying that the experimental results are in good agreement with our DPD results. Mechanical property tests revealed that in blends with equal middle blocks, high elastic recovery was achieved at both f PS = 0.30 and f PS = 0.39. In blends with unequal middle blocks, remarkably increased elongation at break, broadened stress-softening region, and exceptionally high elastic recovery were achieved. Our work demonstrates that blending through rational design enables highly tunable mechanical properties in ABA-type TPEs. Furthermore, this study establishes a correlation between the mechanical behavior and phase separation structures of ABA-type TPEs.

ObjectiveTo address the prevalent issue of the separation between ideological and political education and professional teaching in the education of the Light Chemical Engineering major, a systematic integration system at the professional level is constructed to fulfill the fundamental task of fostering virtue and nurturing talent. AnalysisBased on the historical inheritance and contemporary mission of the light industry, this study has distilled a core indicator system of "Twenty Professional Ideological and Political Principles" covering dimensions such as "patriotic sentiment", "craftsman spirit", and "green development", and established a three-dimensional mapping matrix of "major - course - ideological and political". Taking this as a starting point, the study systematically promotes the coordinated development of ideological and political education and professional teaching from three levels: top-level design of course clusters, reconstruction of course objectives, and implementation of classroom teaching. It also deeply integrates the concepts of new engineering discipline construction and the requirements of professional certification in engineering education to collaboratively solve the three core issues of "education goals", "knowledge system", and "learning paradigm". ConclusionPractical application shows that this integrated education system effectively enhances the high-level nature and educational effectiveness of courses, significantly promoting the simultaneous improvement of students' comprehensive qualities and professional abilities, and providing a replicable and scalable systematic approach for the ideological and political construction of related light industry majors.

Surface-enhanced Raman scattering (SERS) technology has emerged as a powerful analytical tool for trace-level environmental pollutant detection, with its performance critically dependent on the physicochemical properties of substrate materials. While noble metal substrates (e.g., Au/Ag) demonstrate superior SERS enhancement through surface plasmon resonance (SPR), their practical deployment is hampered by inherent limitations including high material costs and susceptibility to oxidation-induced degradation. Herein, we report the rational design of Ag2O/TiO2 composite substrates via a facile wet-chemical precipitation method, wherein Ag2O nanoparticles are uniformly decorated onto pre-synthesized TiO2 nanospheres. Upon application in crystal violet (CV) detection, the optimized Ag2O/TiO2 composite substrate exhibits remarkable SERS performance with an enhancement factor (EF) of 6.7 × 106 and an ultra-low detection limit (LOD) of 1.0 nM (1.0 × 10⁻9 M). Systematic investigations reveal that the Ag2O modification induces photogenerated electron accumulation on the TiO2 surface, promoting photoinduced charge transfer (PICT) between the substrate and adsorbed CV molecules. This work not only presents a cost-effective and stable SERS platform for environmental contaminant monitoring but also provides mechanistic insights into the rational engineering of semiconductor-based SERS substrates with enhanced sensitivity and durability.

The extensive inter- and intramolecular hydrogen-bonding networks among microcrystalline cellulose (MCC) necessitate the development of highly effective solvent systems. In this work, two dihydroxyl pyridinium-based ionic liquids (ILs), namely 3-(hydroxymethyl)-1-(3-hydroxypropyl)-pyridinium chloride ([QPM][Cl]) and 3-(hydroxymethyl)-1-(6-hydroxyhexyl)-pyridinium chloride ([QHM][Cl]), were designed and evaluated for MCC dissolution. Their thermal stability, viscosity, and density were found to decrease when the alkyl chain extended from hydroxypropyl to hydroxyhexyl. Furthermore, at the same temperature, MCC dissolved faster in [QPM][Cl] than in [QHM][Cl], which was consistent with the density functional theory (DFT) calculations that revealed stronger hydrogen-bonding interactions between [QPM][Cl] and cellobiose. Specifically, the average hydrogen bond length in the cellobiose-[QPM][Cl] (2.032 Å) was shorter than that in the cellobiose-[QHM][Cl] (2.056 Å), and the interaction energy (ΔH) value of [QPM][Cl]-cellobiose (-515.054 kJ/mol) was lower than [QHM][Cl]-cellobiose (-509.897 kJ/mol). Atoms in Molecules (AIM) and Reduced Density Gradient (RDG) analyses further confirmed that stronger non-covalent interactions in the [QPM][Cl]-cellobiose system. These results provide molecular-level insights into the role of cation alkyl chain length and hydroxyl groups in cellulose dissolution, guiding the rational design of functional ILs for cellulose-based materials.

Antibiotics are currently the most commonly used therapy for bacterial infections. The evolution of antibiotic resistance has been recognized as an emerging threat to public health. Among the most widely used antibiotics, (3-lactam antibiotics possess the advantages of low toxicity and excellent clinical efficacy. (3-Lactamases confer resistance to (3-lactams by hydrolyzing nearly all of them. Here, we report a new antibiotic nanoadjuvant selfassembled by a maltohexaose-modified poly(5-methyl-trimethylene carbonate-benzoxaborole), which is used to counteract the catalytic activity of (3-lactamase. This nanoadjuvant enables to capture and enter into drugresistant K. pneumoniae through specific recognition of maltose moiety. Benzoxaborole on the adjuvant particle surface inhibits the activity of class C (3-lactamases through a covalent and reversible binding mechanism, thereby restoring bacterial sensitivity to antibiotics without inducing resistance. This nanoadjuvant as a carrier, facilitates the internalization of antibiotics into bacterial cells, enhancing bacterial killing efficiency. The (3-lactam sensitivety to drug-resistant bacteria and decreased inflammatory reactions were further confirmed in a mouse pneumonia model infected with drug-resistant K. pneumoniae after the treatment of nanoadjuvants. This work provides an innovative resensitizing (3-lactam strategy for fighting bacterial resistance to antibiotics using a multivalent nanoadjuvant to repress (3-lactamase activity, and thus markedly enhance the efficacy of antibiotics.

Four hydroxyl-based ionic liquids, 1-methyl-3-(3-hydroxypropyl)-imidazolium chloride ([POM][Cl]), 1-methyl-3-(6-hydroxyhexyl)-imidazolium chloride ([HOM][Cl]), 1-(2-hydroxyethyl)-3-(3-hydroxypropyl)-imidazolium chloride ([DPE][Cl]), and 1-(2-hydroxyethyl)-3-(6-hydroxyhexyl)-imidazolium chloride ([DHE][Cl]), were prepared for starch dissolution. Corn starch dissolution features in hydroxyl-based ionic liquids were evaluated. Density functional theory (DFT) calculations were utilized to elucidate the starch dissolution mechanism. The viscosity and density of hydroxyl-based ionic liquids increased with the second hydroxyl group introduction, while decreased as comparison of hydroxypropyl to hydroxyhexyl group. At the same temperature, the complete corn starch dissolution time in hydroxyl-based ionic liquids followed: [DPE][Cl] < [DHE][Cl] < [POM][Cl] < [HOM][Cl]. The different starch dissolution feature was attributed to the different hydroxyl group numbers and alkyl chain length in imidazolium cation. Two hydroxyl groups of imidazolium cation ([DPE]+) demonstrated three strong O-H‧‧‧O hydrogen bonds with maltose. The average hydrogen bond length of maltose-[DPE][Cl] (1.929 Å) was shorter than maltose-[DHE][Cl] (2.077 Å). Maltose-[POM][Cl] (2.085 Å) was shorter than maltose-[HOM][Cl] (2.197 Å). Hydrogen bonding information, interaction energy (ΔH), Noncovalent interaction (NCI) analysis, and Electrostatic potential (ESP) analysis from DFT calculations demonstrated that cation-maltose, ionic liquid-maltose interactions increased with the second hydroxyl group introduction, while decreased as comparison of hydroxypropyl to hydroxyhexyl group. This information will provide knowledge concerning the design and development of hydroxyl-based ionic liquids for starch dissolution and broaden the industrial application of starch-based materials.

A single-component amphiphilic hydrogel with internal interfacial architecture enables volumetric solar evaporation, delivering high flux via molecularly embedded photothermal units and dynamic air–water interfaces beyond surface-limited designs.

Polymerization-induced self-assembly (PISA) has gained widespread recognition as a potent tool for accessing nano-objects with diverse morphologies. To facilitate its practical application, further development of the self-assembly method is still urgent and challenging. We herein report an innovative self-assembly approach termed heat-induced self-assembly (HISA), enabling the preparation of nano-objects with abundant morphologies by direct thermal dissolution of solid block copolymers (BCPs) in selective solvents at elevated concentration (20% w/w). The BCPs of polyisoprene-b-polystyrene (PI-b-PS), polyisoprene-b-poly(methyl methacrylate) (PI-b-PMMA), and polyisoprene-b-poly(4-vinylpyridine) (PI-b-P4VP) were prepared by living anionic polymerization (LAP) for HISA investigation. Furthermore, this methodology was extended to heat-induced cooperative assembly (HICA) comprising PI-b-PS m /PS n (AB m /B n ) and PI-b-PS m /PI-b-PS n (AB m /AB n ), where B represented the PS core-forming block. The feasibility of HISA and HICA processes was investigated, and a library of morphologies, including spheres, worms, vesicles, nanotubes, and sponges, were collected. The pseudophase diagrams were constructed for both AB m /B n and AB m /AB n systems to provide guiding principles for the tailored morphologies. To evaluate the universality of HISA and HICA techniques, the AC m /C n and AB m /AC n systems (C represented PMMA or P4VP core-forming block) were further investigated. The corresponding glass transition temperatures (T gs) of BCPs in both dry and solvated states were analyzed to gain further insights into the HISA and HICA techniques. These high-concentration assembly strategies including HISA and HICA combined operational simplicity with morphological diversity, showing significant potential in practical applications.

Triple-negative breast cancer (TNBC) remains a formidable clinical challenge due to its aggressive behavior, lack of therapeutic targets, and poor prognosis. The PI3K/AKT/mTOR pathway is highly activated in TNBC, making it a promising therapeutic target. Conventional PEGylated nanocarriers often face challenges, such as accelerated blood clearance and lysosomal trapping. To overcome these limitations, we developed a zwitterionic block copolymer, poly(2-(N-oxide-dimethylamino)ethyl methacrylate)-block-poly(ε-caprolactone) (OPDMA-PCL), via one-pot living anionic polymerization followed by postmodification. Compared with poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-PCL) micelles, the OPDMA-PCL micelles exhibited prolonged systemic circulation, improved tumor targeting, and negligible immunogenicity. OPDMA-PCL micelles exhibited mitochondria-targeting properties in vitro. Loaded with gambogenic acid (GNA), OPDMA-PCL-GNA induces apoptosis in MDA-MB-231 cells by inhibiting the PI3K/AKT/mTOR pathway. In vivo, OPDMA-PCL-GNA achieved 91.2% tumor growth inhibition in xenograft models without systemic toxicity. This work establishes zwitterionic OPDMA-PCL micelles as a promising platform for TNBC therapy, overcoming key limitations of PEGylated systems while enabling organelle-specific drug delivery.

Harnessing the preparation and application of nano-objects with defined compositions and functions has much importance in advanced material fields. Although the scalable production of nano-objects has been accelerated by the efficient polymerization-induced self-assembly (PISA) process, more powerful self-assembly processes are still pursued. In this contribution, the modification-induced self-assembly (MISA) of poly(styrene)-b-poly(4-hydroxystyrene) (PS-b-PtBOS) diblock copolymers was studied by employing trifluoroacetic acid (TFA) as a modifying reagent and toluene as a selective solvent. Furthermore, to enrich the morphological formation window and enhance the MISA process, a modification-induced cooperative assembly (MICA) process was derived by synergistically incorporating the PS-b-PtBOS block copolymers and the PtBOS homopolymer into the same system. By comprehensively optimizing the degree of polymerization of PtBOS (DPPtBOS) and the PtBOS homopolymer content, the morphologies could be modulated in a broad window. Especially, the rarely observed sponge-like morphology was also captured in the MICA system. Additionally, employing the efficient reaction between the phenolic hydroxyl group and formaldehyde, the PHOS core can be stabilized and a phenolic formaldehyde resin-based nano-object could be generated. The MISA or MICA processes greatly facilitated the preparation of nano-objects, which have potential as novel advanced materials.

A single-pass continuous-flow electrochemical oxidation method has been developed for the synthesis of aromatic ketones from alkylarenes and diarylmethanes by utilizing 0.5 equiv of LiClO4 as the supporting electrolyte and water as a safe oxygen source in a mixture of acetonitrile and water. The reactions were conducted in a commercially available undivided flow microreactor equipped with a graphite plate anode and a platinum plate cathode, providing a broad range of aromatic ketones within a short residence time of 25 min. No additional electrocatalysts, redox mediators, additives, or chemical oxidants were required, highlighting the environmental friendliness and sustainability of this continuous-flow electrochemical protocol. Furthermore, the synthetic utility of this approach has been demonstrated by the gram-scale syntheses of a Celestolide derivative, a Fenofibrate derivative, and an anthraquinone.

High exhaustion chromium tannage is an important method to curb the environmental pollution of traditional chrome tanning process. One diketone dicarboxylic acid, 3,3-diacetyl-pentanedioic acid (DAPA) was proposed and applied for high exhaustion chromium tanning process. The chromium content of effluent liquor from DAPA4 method (394.8 mg & sdot;L- 1) was much lower than that of Control method (1223.7 mg & sdot;L- 1). Chromium uptake ratio of DAPA-4 method (90.13 %) was much higher than that of Control method (69.41 %). The tensile strength (Ts), tearing strength, and bursting strength values of leather sample from DAPA-4 method were higher than those of Control method. COD and TDS of effluent liquor from DAPA-4 method was 2193.0 mg/L and 30154.0 mg/L. The high exhaustion chromium tanning mechanism of DAPA including collagen modification and coordination reaction was analyzed from experimental and Density Functional Theory (DFT) simulations. Chemical reaction between diethyl-3,3-diacetylpentanedioate (DAPD) and guanidine carbonate resulted as pyrimidine derivative (4,6-dimethyl-2-imino-5,5-diethyl-acetate-pyrimidine, MDES). Collagen modification of DAPA upon white hide powder was determined. The effect of molar ratio, temperature, and pH value on coordination products formed between DAPA and trivalent chromium ion was analyzed. The beta-dicarbonyl group of DAPA will react with guanidine group of arginine (Arg) to form a pyrimidine derivative, which result in collagen modification and introduce two carboxylic acid (-COOH) groups into collagen fiber. The introduction of -COOH group into collagen enhances the chromium uptake. This work will shed light on design and preparation of high exhaustion chromium tanning agent, also show practical application for sustainable chrome-less leather production.