Removal of Dye Using Lignin-Based Biochar/Poly(ester amide urethane)Nanocomposites from Contaminated Wastewater

The pursuit of incorporating eco-friendly reinforcing agents in polymer composites has accentuated the exploration of various natural biomass-derived materials.The burgeoning environmental crisis spurred by the discharge of synthetic dyes into wastewater has catalyzed the search for effective and sustainable treatment technologies.Among the various sorbent materials explored,biochar,being renewable,has gained prominence due to its excellent adsorption properties and environmental sustainability.It has also emerged as a focal point for its potential to replace other conventional reinforcing agents,viz.,fumed silica,aluminum oxide,treated clays,etc.This study introduces a novel class of polymer nanocomposites comprising of lignin-based biochar particles and poly(ester amide urethane)matrix via a feasible method.The structural evaluation of these nanocomposites was accomplished using Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,and powder X-ray diffraction.The polymer nanocomposites exhibited superior mechanical properties with an increment in tensile strength factor by 45%in comparison to its pristine matrix,along with an excellent toughness value of 90.22 MJm^(−3)at a low loading amount of only 1 wt%.The composites showed excellent improvement in thermal properties with a sharp rise in the glass transition temperature(Tg)value from−28.15℃to 84℃,while also championing sustainability through inherent biodegradability attributes.Beyond their structural prowess,these polymer nanocomposites demonstrated excellent potential as adsorbents,displaying efficient removal of malachite green and tartrazine dyes from aqueous systems with a removal efficiency of 87.25%and 73.98%,respectively.The kinetics study revealed the pseudo second order model to be the precision tool to assess the dye removal study.Complementing this,the Langmuir adsorption isotherm provided a framework to assess the sorption features of the polymer nanocomposites.Overall,these renewable biochar integrated polymer matrices boast remarkable recovery capabilities up to seven cycles of usage with an excellent dye recovery percentage of 95.21%for the last cycle,thereby defining sustainability as well as economic feasibility.

In Vitro Antimicrobial Activity Study of Some New Arginine-based Biodegradable Poly （Ester Urethane）s and Poly （Ester Urea）s

Bactericidal activity of some arginine based biodegradable polymers-PEURs （poly （ester urethane）s） and PEUs （poly （ester urea）s） with low cytotoxicity was studied in in vitro experiments. Various bacterial strains both Gram-positive and Gram-negative were used to explore the bactericidal activity of the cationic polymers. As the test objects, the following microorganisms were used： Bacillus subtilis, Staphylococcus aureus, Mycobacterium album, Pseudomonas fluorescens, Escherichia coli, Actinomyces griseus and Aspergillus niger. The obtained results showed that the new cationic polymers suppressed the growth of the studied microorganisms and the bactericidal activity of the tested cationic polymers strongly depending on their chemical structure.

Fluorinated Hyperbranched Poly(urea-urethane)s Containing Reactive Groups: Synthesis, Characterization and Application on Cotton Fabric

A series of hyperbranched poly(urea-urethane)s (HPUs) containing short fluoroalkyl chain and reactive groups (HPUFs) capable as hydrophobic and oleophobic coating materials were synthesized. The obtained polymers were characterized by FTIR(fouier transform-infrared spectroscopy), 1H NMR(nuclear magnetic resonance), 13C NMR, 19F NMR, GPC(gel permeation chromatography), TGA(thermogravimetric analyzer), and XPS(X-ray photoelectron spectroscopy) analyses. Highly hydrophobic and oleophobic cotton fabrics could be achieved from these fluorinated hyperbranched polymers by solution-immersion coating method. The static contact angles reached to 143°, 114°, and 92° for water, hexadecane, and decane, respectively. The water and oil repellency ratings were 90 and 6, respectively, and still kept 80 and 5, respectively, after 10 soaping cycles at 50℃.

LARGELY IMPROVED BLOOD COMPATIBILITY OF POLYURETHANE BY BLENDING WITH FLUORINATED PHOSPHATIDYLCHOLINE POLYURETHANE

The improvement of biocompatibility of polyurethanes was investigated.The results demonstrate that the blood compatibility of polyurethanes can be further improved by just simply mixing with the fluorinated phosphatidylcholine poly(carbonate urethane)s(FPCPCUs).The solution blending was done by mixing poly(ether urethane)(PEU)with FPCPCU in different compositions.An increased blood compatibility of the blend films was observed with the increase of FPCPCU content,and when FPCPCU content reached to 40 wt%(40F...

SELF-ASSEMBLED MICRO-DOMAINS ON THE UPPERMOST SURFACE OF FLUORINATED POLY(CARBONATE URETHANE)S WITH FLUORINATED SIDE CHAIN ATTACHED ON HARD SEGMENTS

The surface phase separated structure of polyurethanes is always desired due to the advantage of better biocompatibility, compared with the homogeneous one. The key issue is how to control and characterize the surface morphology. In this work, we report the uppermost surface morphology of fluorinated poly(carbonate urethane)s with fluorinated side chains attached to hard segments as studied by AFM, XPS and contact angle measurement. A self-assembled micro-domain with the fluorinated side chain standing up on the uppermost surface has been proposed for polyurethane with higher fluorinated content, based on the result obtained.

Silk Fibroin-modified Poly(butadiene) urethane Films and Their Effects on Fibroblast Viability

Surface-modified poly(butadiene)urethane (PBTU) films with silk fibroin (SF) were prepared by simple chemical method under the normal temperature. The physical properties and biological behaviour of the SF-modified PBTU film were evaluated. The results showed that the SF-modified PBTU films kept the tenacity and pliability very well, and could overcome rigid and brittle weaks of silk fibroin films. The morphology of SF in the PBTU film was dendritic aggregations, and the water-contact angle measurement indicated that the surface hydrophilicity of modified films was apparently enhanced. The biocompatibility of PBTU films was improved due to the change of surface components. The degree of platelet adhesion and the cell viability of rat embryo dermal fibroblasts seeded on PBTU films, SF films, and SF-modified PBTU films were measured by counting platelets before and after they contacted the films and MTT assay, respectively. The results indicated that platelet adhesion resistance and cell viability on the modified film were greatly superior to those on the PBTU film and the compound interface had good stability in the air.

Synthesis and Characterization of a Novel Aqueous Dispersion Poly[urethane-(disperse blue 14)-urethane] Dye

A novel polymeric dye of aqueous dispersion poly[urethane-(disperse blue 14)-urethane] was synthesized based on poly(propylene glycol) (PPG), 2, 4-tolylene diisocyanate (TDI), klimethylol propionic acid (DMPA), disperse blue 14 and triethylamine (TEA) depending on a modified acetone process. Fourier transform infrared spectroscopy (FTIR) was used to identify Lhe structure of the polymeric dye, indicating an obvious carbonyl stretching absorption in disperse blue 14. The polymer was also characterized by the analysis of DSC, TGA, WAXD and UV-Vis spectroscopy.

Surface Modification of Polycarbonate Urethane by Covalent Linkage of Heparin with a PEG Spacer

Heparin was grafted onto polycarbonate urethane (PCU) surface via a three-step procedure utilizing α, ωdiamino-poly(ethylene glycol) (APEG, M n =2 000) as a spacer. In the first step, isocyanate functional groups were introduced onto PCU surface by the treatment of hexamethylene diisocyanate (HDI) in the presence of di-n-butyltin dilaurate (DBTDL) as a catalyst. In the second step, APEG was linked to the PCU surface to obtain the APEG conjugated PCU surface (PCU-APEG). In the third step, heparin was covalently coupled with PCU-APEG in the presence of N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylamidopropyl) carbodiimide (EDAC). The amount of heparin (1.639 μg/cm 2 ) covalently immobilized on the PCU-APEG surface was determined by the toluidine blue method. The modified surface was characterized by water contact angle, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The hemocompatibility was preliminarily studied by platelet adhesion test. The results indicated that heparin was successfully grafted onto the PCU surface, and meanwhile the hydrophilicity and hemocompatibility of the modified PCU surface were improved significantly compared with the blank PCU surface.

PREPARATION AND MECHANICAL PROPERTIES OF POLY(METHYL METHACRYLATE)/ URETHANE ACRYLATE COPOLYMERS

The urethane acrylate(UA) was made of poly(tetramethylenc oxide), 4,4’-diphenylmethane diisocyanate, and 2-hydroxyethyl methacrylate. A series of poly(methyl methacrylate) / urethane acrylate copolymers was prepared by using a redox initiating system. The copolymers had cross linked structures and two-phase morphologies as indicated by the results of the dynamic mechanical measurement and swelling test.

The Effect of Interfacial Interactions on a Structure and Properties of Polyurethane Elastomer/Poly(Vinyl Chloride) Blends

The effect of chemical structure of segmented poly(urethane-urea)s on its interfacial interactions with poly(vinyl chloride) as well as supramolecular structure and the properties of prepared composites has been studied. A direct influence of flexible and rigid segments of elastomers on a compatibility, structure and the physical-mechanical properties of poly(urethane-urea)/poly(vinyl chloride) blends was investigated. A formation of intermolecular hydrogen bonds network in the poly(urethane-urea)/poly(vinyl chloride) systems was evaluated by FTIR analysis. Morphology studies have shown the effect of interfacial interactions on a size of thermoplastic phase dispersed within elastomer matrix. Obtained poly(urethane-urea)/poly(vinyl chloride) micro- and nanocomposites have improved tensile properties.

Electrode Effects on Polyurethane Soft Actuator

A polymer soft actuator is under investigation using a poly urethane elastomer film that bends by means of an applied voltage, which is based on the electrostriction. Bending experiments were performed under different metal electrodes deposited the both sides of the film. Even if the thickness of the both electrodes?is the same, the metal of the both electrodes?is desirable to be the same to bend more. It is suggested that the balance of the physical properties of the both metal is critical for larger bending.

Response to Applied Voltage to Polyurethane Soft Actuators with Loaded Weights

We are investigating a polymer soft actuator using a poly urethane elastomer film that bends by an applied voltage, which is based on the electrostriction. In this article, the bending magnitude was studied in a weight-loaded condition. It was found that the thinner film can bend the more without any load, but that the film of 200-μm thickness gave the largest bending when weights were loaded. The thickness of some degree is critical for large bending torque.

Synthesis and Properties of Thermoplastic Polyisocyanurates:Polyisocyanuratoamide,Polyisocyanurato(Ester-Amide)and Polyisocyanurato(Urea-Ester)

It has been proved that introducing isocyanurate into polymer chains could improve the flame retardancy of polymers.We describe in this work the synthesis and the thermal property study of three thermoplastic polyisocyanurates,which are polyisocyanuratoamide(PICA-6),polyisocyanurato(ester amide)(PICEA-6)and polyisocyanurato(urea ester)(PICUE-6).These polymers show similar and improved thermal stability with the existence of isocyanurate rings.PICA-6 is more crystalizable than the rest two and the melting temperature is found to be around 240℃ but it still crystalizes slowly.For PICEA-6 and PICUE-6,only glass transition can be observed on the DSC traces.The glass transition temperature follows the order of PICA-6>PICEA-6>PICUE-6(101.9,77.9 and 28.7℃,respectively).

Urea Amperometric Biosensors Based on Nanostructured Polypyrrole and Poly Ortho-Phenylenediamine

Urea Amperometric biosensor was obtained on the base of nanostructured polypyrrole (PPy) and poly ortho- phenylenediamine (POPDA). The optimal conditions for monomer electropolymerization were determined. The effect of supporting electrolyte and number of deposition cycles on the OPDA and Py electropolymerization were studied. It was proved that POPDA and PPy were affected by pH changes and responded to the ammonium, product of urease catalyzed reaction. SEM images of the modified Pt/PPy electrode were presented. The cycle voltammograms and chrono amperometric curves of Pt/POPDA/urease and Pt/PPy/urease electrodes were studied. A good linear relationship was observed for Pt/POPDA/urease electrode in a concentration range from 6.7 to 54 mMurea. For Pt/PPy/urease electrode the linear relation in the range from 0.02 to0.16 mMurea was determined. The entrapped carbon nanotubes (CNT) in PPy film and the bipolymer layers were prepared for construction of Pt/PPy/CNT/urease, Pt/POPDA/PPy/urease and Pt/PPy/POPDA/urease biosensors. Obviously, the addition of POPDA to the composition of the two biosensors (Pt/PPy/POPDA/urease and Pt/POPDA/PPy/urease) reduced their sensitivity to urea. Pt/РPy/CNT/urease and Pt/РPy/ urease biosensors were 173 and 138 times more sensitive to urea than biosensor without PPy (Pt/POPDA/urease biosensor). It was found, that the performance of Pt/PPy/CNT/urease electrode was the best from the five obtained biosensors: linear range of urea concentrations—from 0.02 to0.16 mM;sensitivity—15.22 μA/mM and detection limit— 0.005 mM urea.

Synthesis of Bis(4'-hydroxyphenyl)-toluene-2, 4-diurethane for Main Chain Liquid Crystalline Poly(urethane-ester)s

A new methodology was advanced that mesogenic cores appeared after theformation of urethane groups and during the monomer-to-polymer transition. A newdiphenol monomer, bis(4'-hydroxy-phenyl)-toluene-2 (BHPTU), was obtainedby the reaction of 2,4-tolulene diisocyanate with hydroquinone in dioxane or N,N-dimethyl-acetandde. The reaction process was monitored by FTIR, and the product was investigated bylH NMR and elemental analysis (EA). A liquid crystalline poly(urethane-ester) was obtainedusing the BHPTU monomer.

SYNTHESIS OF POLY ( ETHER-URETHANE) CONTAINING PENDANT AMINO GROUP

This paper is concerned with the synthesis of poly (ether-urethane) with pendant amino groups. The copolyether produced by ring opening copolymerization of tetrahydrofuran and epibromohydrin was treated with sodium azide in dimethylformamide to form azido substituted copolyether. The poly (ether-urethane) made from it was subjected to reduction reaction to convert azido group to amino group. The stress-strain behavior and dynamic-mechanical properties of poly (ether-urethane) containing pendant amino groups were studied.

Organosoluble and Thermally Stable of Benzazole-Containing Poly(Imide-Urea)s: One-Pot Synthesis and Characterization

The preparation of new types of poly(imide-urea)s (PIUs) with high thermal stability and improved solubility was investigated. Three series of aromatic poly(imide-urea)s (PIUOa-c, PIUSa-c, and PIUNa-c) bearing pendent benzoxazole, benzothiazole or benzimidazole rings were prepared by one-pot polycondensation reaction of three bis(imide-carboxylic acid)s, 2-[3,5-bis(N-trimellitimidoyl)-phenyl]benzoxazole (1O), 2-[3,5-bis(N- trimellitimidoyl)-phenyl]benzothiazole (1S), or 2-[3,5-bis(N-trimellitimidoyl)-phenyl]benzimidazole (1N) with various kinds of aromatic diamines (a-c). The effects of the benzazole pendent groups on the polymer properties such as solubility and thermal stability were investigated by comparison of the polymers. All of the resulting polymers exhibited excellent solubility in common polar solvents. The glass transition temperature of the polymers determined by DSC thermograms were in the range 192℃ - 236℃. The temperatures at 10% weight loss from their TGA curves were found to be in the range 390℃ - 441℃ in nitrogen.

沥青路面水性聚氨酯丙烯酸热反射涂料制备

以异佛尔酮二异氰酸酯(IPDI)、聚丙二醇(PPG)等原料制备水性聚氨酯(WPU),通过丙烯酸单体和交联剂改性WPU制得水性聚氨酯丙烯酸(WPUA)乳液。利用傅里叶变换红外光谱(FTIR)分析WPUA的官能团,利用铅笔硬度和百格划线法对WPUA膜的硬度、附着力进行测定,利用水接触角试验对WPUA膜的疏水性能进行测试;以降温值、黏度值、光泽度作为评价指标,借助正交试验设计确定WPUA热反射涂料的最佳配方;通过室内太阳辐射模拟装置以及室外太阳照射试验对WPUA热反射涂料的降温效果进行测试。结果表明,WPUA膜的附着力和硬度均得到提高,具有较好的疏水性;WPUA热反射涂料的最佳制备配方为固含量30%的WPUA乳液、16%的金红石型钛白粉、2%的石英砂和4%的中空玻璃微珠。WPUA热反射涂料室内外降温效果显著。

生物基聚脲酰胺的制备及性能研究

采用一锅两步法熔融缩聚合成了高强高韧的生物基聚脲酰胺(PUA)材料。在无催化剂及无溶剂的条件下,先将尿素与1,10-癸二胺反应合成新型生物基单体二(氨基十亚甲基)脲(DADU),并进一步与1,10-癸二酸(DA10)、1,12-十二碳二酸(DA12)或二聚酸(DmA)熔融缩聚制备了一系列高性能PUA。核磁共振氢谱和傅里叶变换红外光谱证明了PUA的链结构,由体积排阻色谱得出PUA的分子量为12~13 kg/mol。PUA可热压成型,并展现了良好的力学性能,拉伸强度和断裂伸长率分别为25~45 MPa和400%~700%。其中PUA-DA10的拉伸强度达到聚酰胺1010(PA1010)的水平,但断裂伸长率是PA1010的2倍以上,可见其韧性远超于PA1010。PUA-DmA的断裂伸长率不亚于PA-DmA,但是其拉伸强度高于PA-DmA,体现出更高的强度和韧性。本研究证实将脲基引入聚酰胺(PA)得到的PUA可以提高材料的力学性能,该方法十分适合生物基聚酰胺的性能改进和多样化设计与应用。

光响应型液晶聚氨酯丙烯酸酯复合薄膜的制备与性能

偶氮苯类化合物在受到特定波长的光照射时,会发生分子结构的异构化,从较稳定的反式结构转变为顺式结构,并且这种光致异构化是可逆的。将偶氮苯基团引入到聚合物结构中可赋予聚合物材料光致变形性能。为了制备光致变形和可形变恢复的多重光响应材料,以2,2'-偶氮二异丁腈为引发剂,通过自由基聚合制备了含有偶氮苯基团的侧链型液晶聚氨酯丙烯酸酯(LCPUA),并通过静电纺丝将其与自制的形状记忆聚氨酯(SMPU)复合制备了复合薄膜,探究了LCPUA与SMPU质量比对复合薄膜性能的影响。结果表明,侧链型LCPUA的热分解温度在250℃以上,具有良好的热稳定性。LCPUA的液晶区间范围较宽,且在四氢呋喃溶液中,具有紫外光响应和可见光恢复性能,其紫外光响应时间为5 s。LCPUA/SMPU复合溶液同样具有紫外光致异构的性质,复合薄膜具有紫外光致变形和可见光恢复的性能,其中LCPUA和SMPU质量比为1∶2时,复合薄膜紫外光响应时间为10 s,光响应速度最快,并且其紫外光响应时间与复合溶液相近。SMPU含量的减少使得复合薄膜的形变恢复能力降低。