Aldehyde-free and bio-based durable coatings for cellulose fabrics with high flame retardancy, antibacteria and well wearing performance.

The bio-based coatings of cellulose fabrics (cotton) had attracted increasing attention for multifunction and sustainability but suffered from poor durability and low efficiency. Here, the aldehyde-free and durable coatings for cotton fabrics (CPZ@CF) with satisfactory flame retardancy, antibacteria as well as wearing performance were prepared through the interfacial coordination effect where the well-organized zinc phytate complex were in situ grew on the pre-treated surface of cotton fabrics with chitosan (CS) and Zn2+. The CZP@CF exhibited excellent antibacterial activity for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with 99.99 % antibacterial rates benefiting from the synergistic effect between Zn2+ and CS. Meanwhile, even the CPZ coatings loading was only 1.5 wt%, the fire safety of CZP@CF remarkably enhanced owing to the excellent synergistic catalytic charring and free radical capture. More importantly, the antibacterial rates of CZP@CF for S. aureus and E. coli still reached 99.99 % and 91.67 % after 50 washing cycles. Additionally, this treatment method did not deteriorate the fabrics properties, including mechanical and breathability as well as wearing performance, which provided the approach to fabricate the flame retardant and antibacterial textiles with well durability and wearing performance.

Facile construction of bio-based high fire-safety cellulose fabrics with well wearing performance.

The design of flame-retardant cellulose fabrics suffered from deterioration on wearing performance and environmental issue. Here, we developed facile construction of bio-based high fire-safety cellulose fabrics (lyocell) that exploited the bio-based flame-retardant coating (APD) by adenosine triphosphate (ATP) and dicyandiamide (DCD) via ionic reaction. The rich phosphorus/nitrogen elements of APD enabled the excellent fire safety of APD/Lyocell. Specifically, the APD/Lyocell2 had a higher limiting oxygen index (LOI) value of 29.3 %, a lower peak of heat release rate (PHRR, decreasing by 66.6 %), and a reduced total heat rate (THR, lowered by 56.5 %) with respect to pure lyocell fabrics. Interestingly, the APD/Lyocell2 exhibited well flame-retardant durability via passing the vertical burning test after 100 rubs. The satisfactory flame-retardant behaviors of APD/Lyocell derived from the excellent synergistic effect on the gaseous-solid phases, where APD could release more non-flammable gasses and generate phosphoric acid, polyphosphoric acid, etc. to accelerate itself and cellulose dehydration into char residues during combustion. More importantly, the wearing performance of APD/Lyocell fabrics, such as handle, air permeability and tensile strength, etc. almost remained after treatment. The ease of operation and use of bio-based coating made it a promising option to obtain the practical lyocell fabrics with flame-retardancy.

Rice straw cellulose microfiber reinforcing PVA composite film of ultraviolet blocking through pre-cross-linking.

Rice straw cellulose microfiber (CMF) was obtained through the gentle low-temperature phase transition method. Then, NaIO4 was utilized to modify CMF by selective oxidation to prepare aldehyde CMF (a-CMF) to improve the reactivity of the CMF. Finally, the a-CMF reinforced polyvinyl alcohol (PVA) composite films were prepared through a pre-cross-linking and solvent casting approach. The cross-linking network formed by a-CMF and PVA through the aldolization reaction significantly improved the mechanical properties of the a-CMF/PVA composite film. The tensile strength of a-CMF-2/PVA was 37.54 ± 0.77 MPa, which was higher than 25.88 ± 2.97 MPa of the pure PVA. SEM results showed that the fracture surface of the a-CMF/PVA composite film with the cross-linking network was smooth. In addition, prepared a-CMF-2/PVA composite films had a transmittance of over 80 % in the visible light range, and also possessed excellent UV blocking property.

Synthesis of Sodium Carboxymethyl Cellulose/Poly(acrylic acid) Microgels via Visible-Light-Triggered Polymerization as a Self-Sedimentary Cationic Basic Dye Adsorbent.

In this study, sodium carboxymethyl cellulose/poly(acrylic acid) (CMC/PAA) microgels were successfully synthesized via visible-light-triggered free-radical polymerization to remove methylene blue (MB) from water. The microgels had a loose and porous 3-D network structure, exhibiting excellent adsorption performance. The equilibrium adsorption capacity and the removal efficiency of the microgels reached approximately 1479 mg/g and 97%, respectively, when the initial concentration of MB was 300 mg/L. The adsorption kinetics was well described by the pseudo-second-order model, and the adsorption isotherms followed the Langmuir isothermal model. Notably, CMC/PAA microgels could naturally settle and be separated from the MB solution. Furthermore, the recovery efficiency of the regenerated CMC/PAA microgels reached approximately 94% after five adsorption-desorption cycles. Therefore, the microgels could be used as promising adsorbents due to the advantages of high adsorption capacity, fast removal rate, and reusability.

Rapid Recovery Double Cross-Linking Hydrogel with Stable Mechanical Properties and High Resilience Triggered by Visible Light.

The designed tough hydrogels, depending on energy dissipation mechanism, possess excellent biocompatibility, stimuli-responsiveness, and outstanding mechanical properties. However, the application of hydrogels is greatly limited in actuators and sensors for the lack of instantaneous recovery and resilience. In this work, we synthesized a double cross-linking poly(acrylic acid) hydrogel via a simple, one-pot, visible-light-trigger polymerization, with carboxymethyl cellulose as initiator and the first cross-linker, N,N'-methylene bis(acrylamide) (MBA) as the second cross-linker. The tensile strength and elastic modulus are in the range of 724-352 kPa and 115-307 kPa, respectively, depending on the MBA content. The swelling ratio of hydrogels dramatically decreased with increasing the MBA content. DMA results indicate that the internal friction between molecules within the hydrogel decreases with the increase of MBA content. Cyclic tensile tests show that after the structure stabilizes, the resilience, maximum stress, and residual strain of Gel-2 maintains over 93% (95% for successive cyclic tensile test), 115 kPa and less than 3%, respectively, at a strain of 125%. The values of resilience and residual strain are almost constant in both successive and intermittent cyclic tensile tests. Moreover, the swollen hydrogel has higher resilience and lower residual strain than the same hydrogel in the as-prepared state.

Late course accelerated hyperfractionated radiotherapy plus concurrent chemotherapy for squamous cell carcinoma of the esophagus: a phase III randomized study.

PURPOSE: Late course accelerated hyperfractionated (LCAF) radiotherapy (RT) is as effective as standard chemoradiotherapy for nonsurgical management of locally advanced esophageal squamous cell carcinoma (SCC). We have evaluated further the efficacy of concurrent LCAF RT and chemotherapy. METHODS AND MATERIALS: In all, 111 eligible patients with esophageal SCC were randomized to receive LCAF alone (LCAF) or concurrent LCAF and chemotherapy (LCAT+CT) between March 1998 and July 2000. All patients received conventional fractionation irradiation of 1.8 Gy per day, to a dose of 41.4 Gy/23 fractions in 4-5 weeks, followed by accelerated hyperfractionated irradiation using reduced fields, 1.5 Gy/fractions twice a day, to a dose of 27 Gy in 18 days. Thus, the total dose was 68.4 Gy/41 fractions in 44 days. Fifty-four patients in the LCAF+CT arm had an additional four cycles of chemotherapy using cisplatin 25 mg/m(2) daily and fluorouracil (5-FU) 600 mg/m(2) daily on Days 1-3 every 4 weeks starting on the same day that LCAF was delivered. RESULTS: The median survival was 23.9 months (95% confidence [CI], 20.1-27.7) for the LCAF arm and 30.8 months (95% CI, 17.6-44.1) for the LCAF+CT arm, respectively. Survival rates at 1, 3, and 5 years of the LCAF arm were 77%, 39%, and 28%, respectively, while those of the LCAF+CT arm were 67%, 44%, and 40%, respectively (p = 0.310). Grades 3 and 4 acute toxicities occurred in 46% and 25% of the patients in the LCAF arm and the LCAF+CT arm, respectively; 6% of the patients in the combined arm had Grade 5 acute toxicities, whereas none was noted in the LCAF alone arm. CONCLUSIONS: Late course accelerated hyperfractionation was effective for locally advanced esophageal SCC. There was a trend toward better survival among patients who received intensified treatment with concurrent chemotherapy. Further randomized studies with a larger number of patients should be carried out, but additional measures must be taken to reduce the higher mortality rate due to chemotherapy-related acute toxicities.

Comparison between continuous accelerated hyperfractionated and late-course accelerated hyperfractionated radiotherapy for esophageal carcinoma.

PURPOSE: To compare the treatment results and toxicity of continuous accelerated hyperfractionated (CAHF) and late-course accelerated hyperfractionated (LCAF) radiotherapy (RT) for esophageal carcinoma. METHODS AND MATERIALS: Between August 1996 and March 1999, 101 patients with squamous cell carcinoma of the esophagus were randomized into two groups: 49 to the CAHF group and 52 to the LCAF group. Patients in the CAHF group received RT at 1.5 Gy/fraction b.i.d. (6-h interval), 5 d/wk, to a total dose 66 Gy in 44 fractions during 4.4 weeks. The patients in the LCAF group received conventional fractionation RT, 1.8 Gy/fraction, to a dose of 41.4 Gy in 23 fractions during 4.6 weeks, followed by accelerated fractionation RT using reduced fields, b.i.d., at 1.5 Gy/fraction, with a minimal interval of 6 h between fractions. The total dose was 68.4 Gy in 41 fraction during 6.4 weeks. Patient age, gender, performance score, diet, lesion location, lesion length, stage, and fractionation (CAHF or LCAF) were entered into the univariate and multivariate analyses. RESULTS: All patients finished the treatment course, except for 1 patient in the CAHF group because of severe acute esophagitis. The rate of Grade I, II, and III acute bronchitis was 18.4% (9 of 49), 30.6% (15 of 49), and 8.2% (4 of 49) in the CAHF group and 13.5% (7 of 52), 21.2% (11 of 52), and 3.8% (2 of 52) in the LCAF group, respectively. However, the difference between the two groups was not statistically significant (p = 0.084). The rate of Grade I, II, III, and IV acute esophagitis was 6.1% (3 of 49), 32.7% (16 of 49), 46.9% (23 of 49), and 14.3% (7 of 49) in the CAHF group and 26.9% (14 of 52), 32.7% (17 of 52), 7.7% (4 of 52), and 1.9% (1 of 52) in the LCAF group, respectively. The difference was statistically significant (p < 0.001). The local control rate at 1, 2, and 3 years was 88.7%, 83.9%, and 55.9% in the CAHF group and 80.7%, 71.4%, and 57.1% in the LCAF group, respectively (p = 0.1251). The 1-, 2-, and 3-year survival rate was 79.6%, 51.6%, and 37.6% in the CAHF group and 80.0%, 57.6%, and 41.2% in the LCAF group, respectively (p = 0.5757). Multivariate analysis showed that age and lesion length were independent significant prognostic factors for local control rate, and age was for the overall survival rate. The fractionation schedule had no significant prognostic effect. CONCLUSION: CAHF and LCAF result in similar 1-, 2-, and 3-year local control and survival rates. CAHF resulted in more severe acute esophagitis and may be less well tolerated than LCAF. The treatment results after the CAHF and LCAF regimens were better than those of historical conventional RT.