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In this paper, the foam-like multi-stage porous 3wt%Al-KIT-6-4T(WI) catalyst was prepared and employed for efficient catalyzing biomass-derived GVL to butene. It is found that the prepared 3wt%Al-KIT-6-4T(WI) catalyst possess abundant mesoporous and presented the foam-like microstructure. Due to this, the 3wt%Al-KIT-6-4T(WI) catalyst has large specific surface area (517.09 m.sup.2·g.sup.-1) and adequate amount of surface acid sites (both Brønsted and Lewis acid site). The special microstructure further improves the mass transfer efficiency of reactants and products. Under the optimized reaction conditions, the butene yield over the 3wt%Al-KIT-6-4T(WI) catalyst can up to 93.78% at 300 °C, after reacting 240 min. Moreover, the 3wt%Al-KIT-6-4T(WI) catalyst still showed excellent regeneration stability, and above 72% butene yield can be maintained after 7th cycle tests.

Considering the current research background of environmental problems and shortages of petroleum resources aiming at proposing the \"green\" polymer blend with good degradability and properties similar to oil-based merchandise currently on the market, in the present study, two series of fully biodegradable blends consisting of PBS/P34HB (PBP) and PBS-g-GMA/P34HB (PGP) have been successfully fabricated by a simple and environmental-friendly processing methodology. In this work, the resulting biodegradable blends are in detail studied from the mechanical, thermal, crystallization, and morphology points of view. To improve the miscibility and enhance the interfacial adhesion between both phases of poly(butylene succinate) (PBS) as the matrix and poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) as the modifier, with consequent improvement in material mechanical properties, glycidyl methacrylate (GMA) is grafted on PBS via reactive blending in the process. The incorporation of 10wt% P34HB into the blend promotes a dramatic increase of 614% in the Izod impact strength. The crystallization temperature (Tc) of PGP is 87.78â when 30wt% P34HB is added, which is 25% higher than that of pure PBS and 11% higher than that of the PBP blend. Meanwhile, the crystallinity of PGP is 30.12%, 47%, and 37% decline compared to pure PBS and PBP, respectively. Rheological results show that storage modulus, loss modulus, and complex viscosity improve significantly with the increase of P34HB amount, indicating that the enhancement of melt strength is beneficial to the processing and forming of the materials.

Nutritional ketosis is a state of mildly elevated blood ketone concentrations resulting from dietary changes (e.g., fasting or reduced carbohydrate intake) or exogenous ketone consumption. In this study, we determined the tolerability and safety of a novel exogenous ketone diester, bis-hexanoyl-(R)-1,3-butanediol (BH-BD), in a 28-day, randomized, double-blind, placebo-controlled, parallel trial (NCT04707989). Healthy adults (n = 59, mean (SD), age: 42.8 (13.4) y, body mass index: 27.8 (3.9) kg/m2) were randomized to consume a beverage containing 12.5 g (Days 0–7) and 25 g (Days 7–28) of BH-BD or a taste-matched placebo daily with breakfast. Tolerability, stimulation, and sedation were assessed daily by standardized questionnaires, and blood and urine samples were collected at Days 0, 7, 14, and 28 for safety assessment. There were no differences in at-home composite systemic and gastrointestinal tolerability scores between BH-BD and placebo at any time in the study, or in acute tolerability measured 1-h post-consumption in-clinic. Weekly at-home composite tolerability scores did not change when BH-BD servings were doubled. At-home scores for stimulation and sedation did not differ between groups. BH-BD significantly increased blood ketone concentrations 1-h post-consumption. No clinically meaningful changes in safety measures including vital signs and clinical laboratory measurements were detected within or between groups. These results support the overall tolerability and safety of consumption of up to 25 g/day BH-BD.

New biodegradable aliphatic PLLA-PBA-PLLA copolymers with soft poly(butylene adipate) (PBA) and hard poly(l-lactide) (PLLA) building blocks were synthesized via ring-opening polymerization (ROP). Proton nuclear magnetic resonance ([sup.1]HNMR) was utilized to confirm the volume fraction of PBA (f[sub.PBA]) within PLLA-PBA-PLLA. It was found that a PBA midblock (PBA-mid) within PLLA-PBA-PLLA-s (PLLA-PBA-PLLA triblock copolymer with a short PLLA block length) might display lamellar domain structure. However, PBA-mid within PLLA-PBA-PLLA-l (PLLA-PBA-PLLA triblock copolymer with a long PLLA block length) might locate itself as a nanoscale cylindrical domain surrounded by a PLLA continuous phase. Polymorphic crystals of PBA-mid within the PLLA-PBA-PLLA copolymers were formed after melt crystallization at the given temperatures, which were studied by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) analysis. According to the WAXD and DSC analyses, it was interesting to find that the α-type crystal of PBA-mid was favorable to develop in the lower temperature region regardless of the state (crystallization or amorphous) of the PLLA component. Additionally, when the PLLA component was held in its amorphous state, it was easier for PBA-mid within the PLLA-PBA-PLLA copolymers to transform from the metastable β-form crystal to the stable α-form crystal. Furthermore, polarized optical microscopy (POM) photos provided direct evidence of the polymorphic crystals of PBA-mid within PLLA-PBA-PLLAs.

The use of renewable bio-based monomers to prepare polyisobutylene-based polymers can not only reduce the dependence on petroleum resources but also promote the green transformation of the cationic polymerization industry. Herein, 2-chloro-2,4,4-trimethylpentane (TMPCl) was synthesized as the main initiator and then cooperated with co-initiator TiCl.sub.4 to construct a cationic initiation system, which was successfully used in preparing poly(isobutylene-co–myrcene). The effects of co-initiator concentration, monomer concentration and monomer feed ratio on the copolymerization of isobutylene (IB) and -myrcene were investigated. The results showed that the molecular weight (M.sub.n) first increased and then decreased with elevating the concentration of TiCl.sub.4. When the monomer concentration was 15 wt% and the monomer feed ratio (mole ratio between IB and -myrcene) was 98:2, an IB-co–myrcene random copolymer with a molecular weight of 7.3 x 10.sup.3 g/mol and a lower T.sub.g (-67.97 â) was obtained. According to the .sup.1H NMR analysis of the polymer structure and terminal groups, it was suggested that IB and -myrcene mainly formed the copolymer with 1,4 structural unit under this initiation system, thus the cationic polymerization mechanism of IB and -myrcene was further proposed. This work can provide basic data and theoretical guidance for the manufacture of greener polyisobutylene-based polymers in the future.

The identification of key active sites that determine oligomerization degree is a key focus of research in olefin oligomerization. The Ni/S-HZSM-5 catalyst has attracted widespread attention due to its excellent performance in this reaction. However, the interaction between SO[sub.4] [sup.2−] and Ni[sup.2+] on the ZSM-5 support, especially quantitatively regulating their ratio, has been rarely investigated. In this study, we prepared a series of Ni/S-HZSM-5-x catalysts by fixing the Ni loading and varying the Ni/S molar ratio in the initial feedstock. Then, the obtained catalysts were characterized to systematically investigate how the Ni/S ratio affects their structure, properties, and n-butene oligomerization performance. The results indicate that tuning the Ni/S ratio enables the targeted regulation of surface acidity and electronic properties of the catalysts. The Ni/S ratio influenced the interaction between the Ni cation and SO[sub.4] [sup.2−]-SO[sub.3] [sup.2−] complex, which in turn altered the Lewis acidity of the catalysts. Further evaluation results reveal that n-butene conversion is positively correlated with the catalyst’s acidity, and the Ni[sup.2+]/Ni[sup.+] ratio is positively correlated with the carbon chain length of the products. The surface form of NiSO[sub.4] is the primary factor determining Lewis acidity, which is directly associated with the chain-growth ability of the catalyst.

Although the adoption of thermoplastic biobased matrix is growing pushed up by environmental issues, the coupling of a Poly(lactic acid) (PLA)/Poly(butylene succinate-co-adipate) (PBSA) blend with hemp fabrics has never been studied. The aim of the present work is to investigate the performance of novel thermoplastic composites reinforced with different amounts of twill hemp fabrics. The effect of different volume fibre content was analysed by tensile, flexural, impact and HDT tests. Analytical predictive models were also applied to forecast the tensile and flexural properties of the biocomposites, paying attention to role of the fibres in warp and weft direction in determining the final mechanical properties of the composites. To better compare the results obtained with the existing composites reinforced with hemp fabrics, a merit index was also calculated to evaluate the efficiency reached by these new composites in terms of stiffness and lightweight.

Biofilm-forming microorganisms pose a severe threat in the food and medical industries, among others. In this paper, the research materials were poly(butylene succinate–dilinoleic succinate) (PBS–DLS) copolymers with variable hard and soft segment weight ratios (90:10, 70:30, and 50:50). Polymeric films were prepared by the solvent casting method. Selected physicochemical properties and the tendency to form biofilm on the polymer surface were investigated. As the amount of DLS soft segments in the polymer matrix increased, changes in the FTIR–ATR spectra (signal intensity), surface (SEM), and phase transition (DSC) were observed. The higher the content of the DLS segment, the lower the transition temperatures and the smoother the film’s surface. These factors resulted in a significant reduction in the amount of biofilm formed on the material’s surface and a decrease in the metabolic activity of microorganisms present in the biofilm and SEM micrographs. The obtained PBS–DLS films have great potential in the food and medical packaging industries.

We report the manufacturing and characterization of poly (butylene succinate) (PBS) and micro cellulose (MCC) woody-like composites. These composites can be applied as a sustainable woody-like composite alternative to conventional fossil polymer-based wood-plastic composites (WPC). The PBS/MCC composites were prepared by using a melt blending of 70 wt% of MCC processed from bleached softwood. MCC was modified to enhance dispersion and compatibility by way of carbodiimide (CDI), polyhydroxy amides (PHA), alkyl ester (EST), (3-Aminopropyl) trimethoxysilane (APTMS), maleic acid anhydride (MAH), and polymeric diphenylmethane diisocyanate (PMDI). The addition of filler into PBS led to a 4.5-fold improvement of Young’s modulus E for the MCC composite, in comparison to neat PBS. The 1.6-fold increase of E was obtained for CDI modified composition in comparison to the unmodified MCC composite. At room temperature, the storage modulus E′ was found to improve by almost 4-fold for the APTMS composite. The EST composite showed a pronounced enhancement in viscoelasticity properties due to the introduction of flexible long alkyl chains in comparison to other compositions. The glass transition temperature was directly affected by the composition and its value was −15 °C for PBS, −30 °C for EST, and −10 °C for MAH composites. FTIR indicated the generation of strong bonding between the polymer and cellulose components in the composite. Scanning electron microscopy analysis evidenced the agglomeration of the MCC in the PBS/MCC composites. PMDI, APTMS, and CDI composites were characterized by the uniform dispersion of MCC particles and a decrease of polymer crystallinity. MCC chemical modification induced the enhancement of the thermal stability of MCC composites.