Increase In Tg Research Articles

Tungsten-Doped Borosilicate Glasses for Radiation Shielding

In this study, a series of glasses in the 25 Na2O- 15 B2O3- (60-x)SiO2- xWO3 system (with x up to 2 mol%) was developed by a melt-quench route. To evaluate their potential applications as novel lead-free transparent shielding materials in nuclear medicine, the impact of tungsten trioxide (WO3) addition on glass formation, structure, properties, and radiation shielding effectiveness of the produced glasses was also investigated. The glass forming ability was found to be restricted, and high-transparency homogeneous bulk glasses containing WO3 up to 1.5 mol% could only be achieved, as verified by XRD measurements. FTIR spectroscopy revealed the network modifications caused by the incorporation of various WO3 concentrations into the glass system. This was further supported by thermal and mechanical investigation, which demonstrated that increasing WO3 content increased both glass transition temperature (Tg) and Vickers hardness (Hv) values. The increases in Tg and Hv could be attributed to tungsten's participation in the formation of new strong W-O connections. Furthermore, the radiation shielding performance of the glasses, such as the half-value layer (HVL), the mean free path (MFP) and the lead equivalent thickness (LEV), as determined by means of a NaI(Tl) scintillation detector in a narrow beam geometry setup using 137Cs, 133Ba and 57Co as the radiation sources, were compared to that of commercial lead glass and found to be improved with higher WO3 content. The findings provide sufficient data to indicate that our tungsten-doped borosilicate glasses, especially the sample containing 1.5 mol% WO3, could be potential candidates for alternative lead-free, high-transparency radiation shielding materials in nuclear medicine applications.

Hyper fibrinolysis state in COVID 19 and its correlation to lipid parameters

BackgroundCoronavirus disease 2019 (COVID 19) is associated with systemic effects involving especially the respiratory and cardiovascular system. The unique features of this condition are disseminated intravascular coagulation, excess fibrin degradation products due to abnormality in the coagulation system that could independently predict mortality. Abberations in lipid parameters that normally predict cardiovascular disease (CVD) were compared with D-dimer levels as risk markers in patients with COVID 19. MethodsA hospital based cross sectional study was conducted over a period of five months in patients aged 30 to 70 years diagnosed with COVID-19. The patients were categorised based on the D-dimer levels as: Group I <0.5μg/ml (Normal), Group II 0.5-2.0μg/ml (Intermediate high), Group III >2.0μg/ml (Very high). The lipid parameters, atherogenic indices were compared between the three groups. ResultsThe mean age of the selected COVID-19 patients was 49.3± 19.1 years of which 63 were males and 37 females (2:1). Significantly high D-dimer levels were detected which had a weak positive correlation with TG, Atherogenic Index Plasma (AIP). Significant rise in TC, LDL and Non-HDL was seen in Group II. Increasing trend of AIP was seen across the groups. D-dimer showed a weak positive correlation with TG, AIP and statistically non-significant negative correlation with rest of the lipid parameters. ConclusionThough an overall increase in D-dimer, TG and AIP was observed in COVID-19 patients, categorization based on D-dimer status detected lowering LDL and increasing AIP on deterioration of disease state.

Influence of exfoliation method of graphene on physical properties of graphene/High Density Polyethylene nanocomposites: Semiconductor‐like electrical conductivity, glass transition, and melting temperature

AbstractDespite the wide range of applications of polyethylene (PE), many efforts are being made to improve its properties with carbon allotropes such as graphene. The addition of graphene can improve the electrical, thermal, and mechanical properties of this polymer. Through the present study, the effects of exfoliated graphene nanoplatelets (XGNPs) and few‐layer graphene (FLG) on the electrical conductivity and thermal properties of high‐density polyethylene (HDPE) were investigated. XGNPs were synthesized by ultrasonication of graphite nanoplatelets, and FLG was synthesized by shear exfoliation of flake graphite. Finally, HDPE powder particles were coated with dispersed XGNPs and FLG. Then XGNPs/HDPE nanocomposites and FLG/HDPE nanocomposites were fabricated by compression molding. The morphology, structural, electrical, and thermal properties of the graphite, graphene, PE, and nanocomposites were observed and comparatively studied by transmission electron microscopy, field emission scanning electron microscope, x‐ray diffraction (XRD), Raman spectroscopy, and conductivity measurements. The graphene's D, G, and 2D bands were revealed by Raman spectroscopy of nanocomposites and verified the existence of the graphene in the polymer matrix. XRD revealed that the graphene did not affect the original crystalline structure of the HDPE matrix, and the Fourier‐transform infrared spectroscopy revealed that the nanocomposite was obtained without the formation of any functional groups. The electrical properties of the nanocomposites were comparatively studied. After adding XGNPs (7 wt%), volumetric electrical conductivity in a sample reached from 10−16 to 10−3 S/m. The highest volumetric conductivity, 1.1 × 10−2 S/m, that is, semiconductor‐like conductivity, was achieved after adding 7 wt% of FLG. The glass transition temperatures (Tg), melting temperatures (Tm), and thermal stability were investigated by differential scanning calorimetry and TGA, respectively, and it was concluded that Tg and Tm increase by adding the graphene. This study shows that shear exfoliation of graphene is the best and the most facile method to prepare mass‐scale graphene for the production of graphene/polyolefin nanocomposites.Highlights Two types of graphene were produced by using sonication and shear‐exfoliation. HDPE powders were coated with two types of graphene and then hot pressed. The method of (G) preparation is crucialparameter on electrical conductivity. In the sample containing 7 wt% (XGNPs), the highest conductivity is 10−3 S/m. In the sample containing 7 wt% (FLG), the highest conductivity is 10−2 S/m.

A-210 Ldl-c to non-hdl-c ratio method: a simple way to determine bias for ldl-c methods on hypertriglyceridemic samples

Abstract Background Beta-quantification (BQ) is the reference method for LDL-C but is not widely available. It is difficult, therefore, for clinical laboratories to independently assess the accuracy of their methods for either calculating or directly measuring LDL-C. Our goal was to investigate if an interrelationship between the tests in the standard lipid panel could be used to compare the performance of different LDL-C methods against BQ, specifically in samples with hypertriglyceridemia, a major cause of bias for LDL-C testing. Methods BQ results from Mayo Medical Labs (n=39,667) and the NIH (n=18,338) were used to identify a linear relationship by least-squares regression analysis between lipid panel test results and LDL-C to facilitate a statistical comparison between different LDL-C methods. Results It is well established that the number of VLDL particles increases as TG increases, because VLDL is the main carrier of TG. As a consequence, the ratio of LDL-C to non-HDL-C is inversely related to TG, which can be made linear by taking the square root of TG (Figure). Nearly identical regression equations were found for this relationship, using two different BQ datasets. When LDL-C was calculated by either Sampson equation, the LDL-C/non-HDL-C regression lines nearly overlapped with the one for BQ. In contrast, the Martin equation showed a positive bias with increasing TG, whereas the Friedewald equation showed a negative bias, consistent with past reports on their LDL-C biases with hypertriglyceridemia. In the UKBiobank, the Beckman direct LDL-C showed a positive bias for TG, which was confirmed in CAP proficiency test surveys. By simulation analysis, approximately 80 samples with high (&amp;gt;200 mg/dL) and low (&amp;lt;100 mg/dL) TG is statistically sufficient to assess if the LDL-C/non-HDL-C regressions lines of LDL-C methods differ from BQ. Conclusions The LDL-C/non-HDL-C ratio method is a simple way to examine LDL-C methods for bias on hypertriglyceridemic samples.

TDAE aromatic oil preference for polymer blends: An analysis of S-SBR, BR, and miscible S-SBR/BR systems

This study assesses the impact of Treated Distillate Aromatic Extract (TDAE) oil, at concentrations of 0–20 parts per hundred rubber (phr), on the glass transition temperature (Tg) of High Vinyl/Low Styrene Styrene-Butadiene Rubber (HVLSS-SBR), polybutadiene rubber (BR), and their blends with weight ratios of 70/30 and 50/50. Using Dynamic Mechanical Analysis, Broadband Dielectric Spectroscopy, and Positron Annihilation Lifetime Spectroscopy, we found that TDAE modifies Tg and fractional free volume (Fv) differently across materials. In HVLSS-SBR, TDAE reduced Tg by approximately 10 °C and increased Fv by 0.8 %. In BR, TDAE raised Tg by 5–7 °C without altering Fv. The 70/30 blend showed no Tg change but a 0.6 % Fv increase. For the 50/50 blend, one Havriliak-Negami equation indicated a Tg rise of 2–3 °C and a 0.4 % Fv increase. A two-equation analysis revealed a 6 °C Tg increase and 0.9 % Fv boost in the BR-rich phase, versus a 2 °C rise and 0.3 % Fv uptick in the HVLSS-SBR-rich phase. The sequence of compatibility, influenced by TDAE, is crystalline BR > amorphous BR > HVLSS-SBR >70/30 blend >50/50 blend. This study provides valuable insights into the behavior of TDAE oil in rubber blends and can serve as a basis for further research in this field.

Pre-operative thyroglobulin measurement for thyroid cancer risk of recurrence and response to therapy

BackgroundThyroid cancer has an overall favorable prognosis, but no pre-operative biochemical marker has been shown to distinguish between low and high-risk disease or predict response to therapy. MethodsWe retrospectively reviewed 162 patients that underwent thyroid surgery for thyroid cancer between 2006 and 2022 in whom a pre-operative thyroglobulin level (Tg) was measured. We subdivided patients into low, intermediate and high-risk thyroid cancer and based on their response to therapy per ATA guidelines. ResultsWe showed that as pre-operative Tg level increased, patients were more likely to have high-risk disease (p ​< ​0.01). We found a linear association between the primary tumor size and high-risk histology with pre-operative Tg (p ​< ​0.01). Pre-operative Tg level was significantly associated with response to therapy following initial surgical management. Specifically, as pre-operative Tg increases, patients were less likely to achieve an excellent response (p ​< ​0.01). ConclusionsOur retrospective analysis demonstrated that pre-operative Tg is significantly associated with ATA structural risk of recurrence and response to therapy and may have the potential to guide initial therapy and follow-up management.

Thermomechanical properties of poly(vinyl alcohol) prepared at room temperature as a function of degree of hydrolysis and aluminium addition

Poly(vinyl alcohol) (PVOH) is widely used in various industrial applications. However, its water solubility reduces film performance, which is important in PVAc-based wood adhesives. In this sector, AlCl3 is often used as a complexing agent for PVOH. In this work, the effect of heating and aluminium addition on the structure and viscoelastic properties of PVOH with different degrees of hydrolysis (DH), 88%, 92% and 99%, was studied. Products treated with either HCl or acetic acid were also considered. The polymer properties were evaluated by infrared spectroscopy and dynamic mechanical analysis, and the mass loss of the polymers on heating was also evaluated to explain the observed differences. The measurements showed that the peaks of the tanδ curves occurred at slightly lower temperatures as the DH increased, although higher crystallinity was observed at the end of the DMA tests for higher DHs. This is due to the increasing affinity of highly hydrolysed PVOH for water molecules. However, as the temperature increased, the storage modulus was higher for higher DHs due to the better mutual interaction of OH groups that develops during the tests in highly hydrolysed polymers. The addition of aluminium caused a slight increase in Tg, the magnitude of which was inversely proportional to the DH. However, as the temperature increased, the storage modulus decreased more at lower DHs than at higher DHs. This effect was related to a combination of factors: the lower presence of crystallites in products with lower DH and the formation of conjugated polyenes, which was also more pronounced in products with lower DH. Both mechanisms were due to the action of aluminium. Thus, both heat and the addition of aluminium had a determining effect on the properties of PVOH films, although the degree of importance depended on the degree of hydrolysis of the polymer.

Kinetics of Plasticized Poly(vinyl chloride) Thermal Degradation, Induction, Autocatalysis, Glass Transition, Diffusion

AbstractKinetics of non‐oxidative thermal degradation of poly(vinyl chloride) (PVC) plasticized with di(2‐ethylhexyl)phthalate and epoxidized linseed oil (ELO) were studied using differential scanning calorimetry. PVC thermal degradation autocatalyzed by forming HCl is delayed in the presence of acid scavenging ELO. Direct HCl elimination rates during steady state degradation (induction period) were almost independent on ELO concentration, with rate constants ranging from ≈3.2×10−6 s−1 at 463 K to ≈7.0×10−5 s−1 at 503 K. Activation energy of HCl elimination increased with glass transition temperature (Tg) increase from 136.0 kJ mol−1 at Tg=260.3 K to 141.9 kJ mol−1at Tg=274.2 K. Diffusion coefficients of HCl diffusion in plasticized PVC deduced using Williams‐Landel‐Ferry equation were of the order of 10−4 cm2 sec−1. Calculated activation energy of HCl diffusion in plasticized PVC was ≈30 kJ mol−1. The rate constants of PVC autocatalytic degradation were derived from the experimental data (for the 1st time) using Šesták‐Berggren approach and ranged from 3.2×10−2 sec−1 at 503 K to 4.4×10−3 sec−1 at 463 K. Autocatalysis activation energies ranged from 70.4 kJ mol−1 to 85.1 kJ mol−1 and increased with increase of glass transition temperature. It was established that PVC degradation kinetics was not controlled by HCl diffusion. Compensation effect was observed for initial and catalyzed PVC degradation.

Reinforcing poly(lactic acid)/poly(butylene succinate) biodegradable blends with silicon carbide (SiC): A silane‐coupled approach for enhanced mechanical and thermal performance

AbstractThis study aims to enhance the properties of biodegradable plastics by blending poly(lactic acid) (PLA) as well as poly(butylene succinate) (PBS) with silicon carbide (SiC). SiC content was varied from 10 to 40 phr using an internal mixer, maintaining a 90/10 wt% ratio of PLA/PBS as the matrix. The investigation covered mechanical, thermal properties, chemical structure, and composite morphology. The morphological analysis confirmed even dispersion of SiC within the PLA/PBS matrix, possibly due to improved compatibility via a silane coupling treatment. This resulted in the maximum Young's modulus and impact strength with 40 phr SiC, showing a 40% and 76% enhancement, respectively, compared to pure PLA. Concerning thermal properties, SiC addition influenced the mobility of PLA/PBS molecular chains and crystalline structure, leading to an increase in Tg with higher SiC fractions. However, ΔHm of PLA, PBS, and Xc,PLA decreased, which corresponds to reduced viscosity in the PLA/PBS blend and increased mobility with higher SiC content, as indicated by the elevated MFI value.Highlights Young's modulus increased by 40% and impact strength by 76% than pure PLA. Even SiC dispersion in PLA/PBS, possibly aided by silane coupling. SiC alters chain mobility, boosts crystalline structure, raising Tg. ΔHm and Xc,PLA reduced, suggests reduced viscosity in PLA/PBS at more SiC. Elevated MFI value shows increased chain mobility in PLA/PBS blend at more SiC.

Active surveillance is a feasible and safe strategy in selected patients with papillary thyroid cancer and suspicious cervical lymph nodes detected after thyroidectomy.

After initial treatment, up to 30% of patients with papillary thyroid cancer (PTC) have incomplete response, mainly cervical lymph node (LN) disease. Previous studies have suggested that active surveillance (AS) is a possible option for these patients. Our aim was to report the results of AS in patients with PTC and cervical LN disease. In this retrospective observational study, we included adult patients treated and followed for PTC, who presented with cervical LN disease and were managed with AS. Growth was defined as an increase ≥ 3mm in either diameter. We included 32 patients: 27 (84.4%) women, age of 39 ± 14 years, all initially treated with total thyroidectomy, and 22 (69%) with therapeutic neck dissection. Cervical LN disease was diagnosed 1 year (0.3-12.6) after initial management, with a diameter of 9.0 mm (6.0-19.0). After a median AS of 4.3 years (0.6-14.1), 4 (12.5%) patients had LNgrowth: 2 (50%) of whom were surgically removed, 1 (25%) was effectively treated with radiotherapy, and 1 (25%) had a scheduled surgery. Tg increase was the only predictive factor of LN growth evaluated as both the delta Tg (p < 0.0366) and percentage of Tg change (p < 0.0140). None of the included patients died, had local complications due to LN growth or salvage therapy, or developed distant metastases during follow-up. In selected patients with PTC and suspicious cervical LNs diagnosed after initial treatment, AS is a feasible and safe strategy as it allows effective identification and treatment of the minority of patients who progress.

Petroleum ether extract of Schisandra sphenanthera prevents hyperglycemia and insulin resistance in association with modulation of sweet taste receptors and gut microbiota in T2DM rats

Ethnopharmacological relevanceSchisandra sphenanthera (Schisandra sphenanthera Rehd. et Wils.) is the dried mature fruit of Schisandra sphenanthera, a plant in the Magnoliaceae family. It was used in the treatment of diabetes mellitus in the Jade Fluid Decoction and the Xiaoke pills, which were recorded in ancient books. However, its mechanism of action in the treatment of type 2 diabetes mellitus (T2DM) was unclear and needs further study. Aim of the studyThis research aimed to investigate the chemical composition and lignan content of Schisandra sphenanthera petroleum ether parts (SPEP) and to evaluate the effects of SPEP on sweet taste receptors (STRs) and intestinal flora in rats on a high-fat diet (HFD). Additionally, the relationships between SPEP and hyperglycemia and insulin resistance were examined. Materials and methodsGC-MS was used to determine the chemical composition of SPEP, and HPLC was used to determine the lignin content. A combination of the HFD and the administration of streptozotocin (STZ) was employed to generate a rat model of T2DM. Petroleum ether extracts from Schisandra sphenanthera were used as the focus of the research to evaluate the effects of these extracts on the glucolipid metabolism of T2DM rats, as well as the underlying mechanisms. ResultsAnalysis of the GC-MS spectrum of SESP revealed a total of 58 compounds. HPLC analysis revealed that SPEP had the highest concentration of Schisandrin A and the lowest concentration of Schisandrol A. The drug administration intervention resulted in a significant decrease in body weight and pancreatic weight of diabetic rats compared to the Normal group. When compared to the Model group, the body weight of rats in the drug administration group and the Metformin group had a more moderate decrease, while the pancreatic weight and pancreatic-to-body ratio increased. The Model group shown significant increases in FBG, OGTT, GHb, TC, TG, LDL-C, ALT, AST, MDA, FINS, and NEFA, as well as significant decreases in HDL-C and SOD, when compared to the Normal group (P < 0.05). The administration of each group was found to be significantly effective in decreasing FBG, OGTT, GHb, TC, TG, LDL-C, ALT, AST, MDA, FINS, NEFA, while increasing HDL-C and SOD when compared to the Model group. The application of SPEP had a positive impact on hepatocyte swelling, hepatocyte degeneration, and necrosis, as well as the morphological structure of pancreatic islet cells. Furthermore, the protein expression levels of T1R2, TRPM5 and GLP-1 in the small intestine of the Model group were reduced. After a period of six weeks, the protein expression levels began to align more closely with those of the Normal group of rats. Analysis of 16S rRNA sequencing revealed that the intestinal microbiota of diabetic rats was significantly disrupted, with a decrease in the abundance of the Firmicutes phylum and an increase in the abundance of the Bacteroidetes phylum. Furthermore, the composition of the dominant genus was distinct from that of the control group. After the drug intervention, the microbiota of diabetic rats was significantly altered, exhibiting a higher abundance and diversity, as well as a significant enrichment of the community. The SPEP treatment resulted in a significant increase in acetic acid, propionic acid, and butyric acid. ConclusionsThe findings of this research indicated that SPEP could be effective in treating T2DM through the regulation of STRs, the adjustment of disturbed metabolite levels, and the alteration of intestinal flora.

Graphene/graphene oxide and melamine as synergistic additives for polyester nanocomposite coatings

Ensuring mechanical robustness is crucial for polyester coatings on pre-coated metal (PCM). The incorporation of nanofillers such as graphene nanoplatelets (GNP) and graphene oxide (GO) has demonstrated potential in enhancing mechanical properties of polymeric nanocomposites. However, the utilisation of these nanofillers in saturated polyester systems remains largely unexplored. Therefore, this study developed polyester-based nanocomposite coatings incorporating GNP or GO and systematically investigated the effects of the nanofiller loading and the hexa (methoxymethyl)melamine (HMMM)/polyester ratio on the properties of the coatings. Adding nanofillers led to the reduction of both glass transition temperature (Tg) and hardness (H) of the coating. Specifically, at a 1:5 HMMM/polyester ratio, Tg reduced from 29.9 °C for plain polyester (Blank) to 26.1 °C and 22.0 °C for polyesters with 5 wt% GNP (A-5.0GNP) and GO (A-5.0GO) respectively; H values also decreased from 274 MPa for Blank polyester to 222 MPa and 143 MPa for A-5.0GNP and A-5.0GO, respectively. The hydroxyl groups on the nanofillers affected crosslinking between HMMM and polyester by reacting with HMMM, thereby reducing the crosslink density of the cured coatings. Increasing nanofiller loading led to a more significant reduction in crosslink density, resulting in decreased Tg and H values. At the same loading level, the significantly higher hydroxyl content of GO had a more pronounced effect in reducing crosslink density compared to GNP. Furthermore, an increase in HMMM compensated for the HMMM loss to GO and facilitated the polyester crosslinking reactions, leading to significant increase in both Tg and H. Specifically, for the 2 wt% GO nanocomposites, Tg increased significantly from 24.7 °C to 32.1 °C with a rise in the HMMM/polyester ratio from 1:5 to 1:2, while the H value increased notably from 193 MPa to 452 MPa.

Effect of apheresis plasma donation on plasma uric acid levels, the lipid profile, and major plasma proteins in plasma donors in China: A multicenter, prospective cohort study

Abnormal plasma uric acid (UA) levels, the lipid profile, and plasma proteins in blood are associated with a range of adverse health outcomes. This multicenter, prospective cohort study aimed to determine the possible effects of multiple apheresis plasma donations on plasma UA levels, the lipid profile, and major proteins in plasma donors. Participants were enrolled from 1 April 2021 to 31 August 2022. When their plasma UA (men: >420 µmol/L, women: >360 µmol/L) and/or lipid levels (total cholesterol [TC]: ≥6.2 mmol/L, triglycerides [TGs]: ≥2.3 mmol/L, low-density lipoprotein cholesterol: ≥4.1 mmol/L, or high-density lipoprotein cholesterol [HDL-C]: <1.0 mmol/L) were abnormal at their first plasma donation, the enrolled participants were followed up until they had completed 10 plasma donations. A total of 11485 participants were enrolled, of whom 1861 met the inclusion criteria. During the study period, 320 donors completed 10 plasma donations. None of the participants took any corrective medicine for their abnormal index. The measured parameters were significantly different from the first to the tenth plasma donations (donors with asymptomatic hyperuricemia: UA, P < 0.001; donors with asymptomatic hyperlipidemia: HDL-C, P < 0.001; TC, P = 0.025; TGs, P < 0.001; apolipoprotein B, P = 0.025; all of the plasma donors, immunoglobulin G, P < 0.001). The levels of HDL-C, TC, and apolipoprotein B were increased, and the levels of UA, TGs, and immunoglobulin G were decreased over this time. However, immunoglobulin G levels were still in the normal range. Moreover, the changes in these parameters were closely associated with the frequency of plasma donation during the study period. Repeated apheresis plasma donations can reduce plasma UA and TG levels and increase HDL-C levels; and further evaluation of the clinical significance with a larger sample size is required.

Correlation of thermal and electrical properties of silver germanophosphate glasses with their structural analysis by Raman and NMR spectroscopy

In present study glasses of the system Ag2O-GeO2-P2O5 were studied in the compositional series (50−x)Ag2O-xGeO2-50P2O5 with x = 0−40 mol%. Ag2O substitution by GeO2 results in a significant increase of both glass transition temperature, Tg, and crystallization temperature, Tc, up to 628 °C (Tg) and 851 °C (Tc) at x = 40 mol% GeO2. The glass structure was investigated from the analysis of 31P MAS NMR and Raman spectra. Both methods show transformation of phosphate glass network formed mainly by Q2 units to germanate-phosphate network formed by Q1xGe and Q21Ge phosphate units and germanate units. Raman spectra, in addition, reveal evolution of P‒O‒P linkages to P‒O‒Ge and Ge‒O‒Ge linkages through the glass series. DC conductivity trend upon GeO2 addition showed non-monotonic behaviour, which is related to structural changes in the glass-network.

Sustainable, transparent, strong toughness, UV resistance, and anti-corrosion properties of cashew shell oil-based waterborne polyurethane network derived from phloretin and sorbitan monooleate-based siloxane

The increasingly severe energy shortage and growing environmental problems have accelerated the rapid development of sustainable polymer materials. Hereon, a novel method was proposed for the synthesis of cashew nut shell oil-based waterborne polyurethane (WPUs), which exhibited excellent toughness, transparency, water resistance, UV resistance and corrosion resistance. Specifically, the sorbitan monooleate-based siloxane (MSP) was prepared via a thiol-ene click chemistry reaction. Subsequently, the plant-based phloretin (PRT) and MSP were introduced as polyols into the skeleton of WPUs through the molecular structure design strategy. Series of high bio-based content (91 %) WPUs networks were obtained via pre-polymerization and self-emulsification methods. The properties of their dispersions and films were thoroughly investigated, and it was found that the addition of MSP and PRT enhanced the overall performance of WPUs film. For instance, there was a significant increase in Tg. Additionally, they exhibited a maximum tensile strength of 31.5 MPa and a maximum toughness of 53 MJ/m3, which were the most outstanding among all reported plant oil-based WPU systems so far, indicating excellent tear resistance. Interestingly, the water absorption rate of PSWPU-40 was reduced to 7.1 %, suggesting good water resistance, which resolved the contradiction between the mechanical properties and water resistance of the current plant oil-based WPU systems. The PSPWU films exhibited promising application prospects, exemplified by its ability to effectively shield the entire UV range. Furthermore, its coating demonstrated outstanding anti-corrosion properties with a maximum anticorrosion efficiency of 97.1 %. It could be attributed to the synergistic effect of a self-crosslinking structure, higher crosslinking density, a tighter network structure, and stronger intermolecular forces (H-bond). This work provided a meaningful guide for the application and development of high-performance bio-based WPU functional coatings.

Tuning the structure of pendant groups in poly(α‐arylTMC)s: A pathway to high glass transition temperature

AbstractAliphatic polycarbonates have been explored as environmentally benign alternatives to aromatic polycarbonates. Improvements to the glass transition temperature (Tg) of aliphatic polycarbonates have been pursued by several groups. We recently showed that attaching a pendant aromatic group to poly(TMC) can enhance the Tg. Also, we have shown that para substituents on the pendant group have an impact on the Tg. Here, we have explored the role of bulky pendant groups and the effect of substituent position on the pendant aromatic ring. We prepared novel naphthalene‐derived poly(TMC)s as well as 2‐Br‐substituted poly(PhTMC). The 2‐bromophenyl derivative showed a Tg of 69.5 °C which represents a nominal increase in comparison to the 4‐bromo derivative that we reported earlier. This suggests that the position of the substituent does not have a critical impact on Tg. With naphthalene derivatives, the increase in steric bulk led to an increase in Tg. Increase of chain length beyond fifty monomer units had a minimal impact on Tg. Finally, when 4‐bromonaphthyl moiety was the pendant group, we observed a Tg of 97 °C. This demonstrates that Tg can be varied significantly by modifying the pendant groups. We have also shown that the 1,3‐diols used in our polymer are non‐cytotoxic.

Effect of Phosphorus-Nitrogen based Flame-Retardant Combined with Zinc Borate on Thermal Stability and Flame Retardancy of Epoxy Clay Nanocomposites

A phosphorus-nitrogen containing 6,6'-(piperazine-1,4-diyl)bis(6H-dibenzo[c,e][1,2]oxaphosphinine 6-oxide) (DOPO-PZ) flame-retardant was synthesized and its effect combined with zinc borate (ZnB) and nanoclay (NC) on thermal stability and flame retardancy of epoxy resin was studied. Various epoxy composites containing DOPO, DOPO-PZ, ZnB and NC using curing agent diaminodiphenylsulfone (DDS) were prepared. The X-ray diffraction (XRD) and transmission electron microscope (TEM) micrographs of the composites showed intercalated nanostructure of epoxy-clay nanocomposites. In thermogravimetric analysis (TGA), pure epoxy gave 3.4% char yield at 700 ºC in nitrogen atmosphere, while in case of EP/DOPO-PZ/ZnB/NC sample having 1% phosphorus content, 5 wt.% zinc borate (ZnB) and 3 wt.% nanoclay (NC), the char yield is increased to 24.0%. Differential scanning calorimetry (DSC) study showed decrease in the glass transition temperature (Tg) on the addition of flame-retardant due to plasticization effect and increase in Tg on addition of nanoclay due to formation of nanostructure of epoxy composites. The EP/DOPO-PZ/ZnB/NC nanocomposite sample exhibited a limiting oxygen index (LOI) value of 29.2% and passed the UL-94 test with a V-0 rating and thus achieved a sufficient flame retardancy.

Role of crosslinkers on the properties of bio‐based wood adhesives

AbstractAs people became more conscious of the risks associated with pollution in the early 21st century, eco‐friendly adhesives made from plant oil began to be used. Bio‐based adhesives are widely used due to their low price, easy accessibility, and high biodegradability; however, their low adhesive strength is an issue. This work incorporates three natural crosslinkers: tannic acid (TA), sorbitol (SR), and cellulose (CL) to address the drawbacks of bio‐based adhesives, such as low adhesive strength, inferior output in humidity and longer curing time that result from excess water. Methylene diphenyl diisocyanate (MDI) was used to react with soybean oil‐based polyol (SOP) plus the crosslinkers to make bio‐based polyurethane adhesives. The maximum bonding strength of the soybean‐based adhesive containing 10 wt.% of SR (SR‐10%) was measured at 6.19 MPa which is about 44% higher than the sample without SR. The higher strength is due to the crosslinking ability of SR. The effect of crosslinking is also observed in the study of polar protic and polar aprotic solvents used to dissolve the adhesive. As compared with the polar aprotic solvent tetrahydrofuran, TA‐containing adhesive samples showed a maximum tensile strength of 3.69 MPa in methanol; a polar protic solvent that can participate in further hydrogen bonding to form a higher crosslinked complex. The glass transition temperature (Tg) increases with the increase in crosslinker amount. The observed increase in Tg may be attributable to an increase in crosslinking density, which reduces polymer chain flexibility and causes a stronger material.Highlights Bio‐adhesives based on soybean oil and diisocyanate were synthesized. Natural crosslinking agents such as tannic acid, sorbitol, and cellulose were used. The effect of crosslinking using polar protic and aprotic solvents was studied. The glass transition temperature increases with the increase in crosslinker amount.

The role of MgO on physical and bioactive properties of borophosphate glasses for biomedical applications

In this work, a novel series of borophosphate glasses of the system 40B2O3–25P2O5–(20-x)Na2O–15CaF2–xMgO (x = 0, 2.5, 5, 7.5, and 10 mol%) were synthesized using the melt-quenching technique. The effect of replacing Na2O with MgO in the glasses was analyzed by the physical and bioactive properties. The glasses were characterized by density, molar volume, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Differential thermal analysis (DTA), bioactivity tests in simulated body fluid (SBF), pH measurements, mass loss, and verification of cellular compatibility in RAW 247 murine macrophages. XRD and FTIR analyses were performed before and after immersion in SBF to verify the bioactivity. Density, molar volume and FTIR results before SBF showed structural changes in the glasses due to the addition of MgO. The pH and mass loss measurements allowed to verify the degradation behavior of the glass series as a function of MgO concentration. The DTA data showed an increase in Tg, Tx, and thermal stability due to the increase in MgO addition. XRD and FTIR analyses after SBF soaking showed superficial formation of apatites and other calcium phosphates of biological interest in the samples, attesting the bioactivity. Cytotoxicity assessed by MTT assay on the cell line RAW 247 showed that at a concentration of 500 μg/mL all glasses were compatible (non-cytotoxic). The results suggest that the synthesized glasses are bioactive, with the sample containing 5 mol% MgO exhibiting the bioactivity and biocompatibility required for biomaterial applications.

Integration of pharmacodynamics and metabolomics to reveal rhubarb anthraquinone protection against nonalcoholic fatty liver disease rat model.

The objective of the present study was to investigate the effect of Rhubarb anthraquinone (RA) on a high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) rat model, and explore potential biomarker and metabolic pathways by using the metabolomics method. We established HFD rats as the NAFLD model. Forty Sprague-Dawley rats were randomly divided into a control group, model group, RA low-dose group, RA medium-dose group, and RA high-dose group, and evaluated the protective effect of RA on NAFLD by detecting biochemical indicators of serum and pathological changes of liver tissue. Investigating potential biomarkers and metabolic pathways connected with RA's protective effects against NAFLD by UHPLC-Q-TOF-MS untargeted metabolomics. The results showed that RA significantly reversed the increase of TG, TC, ALT, AST, and ALP (P < .05), the decrease of HDL-C (P < .05), and alleviated pathological conditions in NAFLD rats. Based on potential biomarker analysis, RA affected metabolic pathways such as fatty acids biosynthesis, bile acids biosynthesis, and pentose phosphate pathway, delaying the progression of NAFLD. RA improved blood lipid levels, liver function, and pathological conditions of NAFLD rats. Meanwhile, affected the metabolic pathways and regulated the synthesis of fatty acids and bile acids in NAFLD rats.