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Several series of alternate poly(amide-imide)s [P(A-alt-I)s] were synthesized by aromatic dicarboxylic acid (I- p or I- m), which was prepared by the condensation of p-phenylenediamine (or m-phenylenediamine), trimellitic anhydride, and various aromatic diamines by means of direct polycondensation. A diimide-diacid (I- p) with a p-phenylene group was used to synthesize P(A-alt-I)s III, and P(A-alt-I)s IV were synthesized by a diimide-diacid (I- m) prepared from m-phenylenediamine. Another series of P(A-alt-I)s V was synthesized from both I- p and I- m (1/1 mole) with various diamines. Polymers of series III have low inherent viscosities and limited solubility, but polymers of series IV have high degrees of polymerization. Series V copolycondensated from I- p and I- m has improved solubility and degrees of polymerization relative to series III. The degree of crystallinity was found to be III > V > IV. Glass transition temperatures for most of series III were not observed below 400 °C, and those of series IV and V were in the range of 238–325 °C and 262–328 °C, respectively. The 10% weight loss temperatures in nitrogen or in air of these three series are all in the range of 482–582 °C. Because series V has limited solubility for casting into films from DMAc solutions, two diamines were selected to synthesize series VI by changing the I- p/I- m ratio. Solubility was improved when the content of I- p in diimide-diacid was less than 15%, and the degree of crystallinity reduced as the content of I- p in diimide-diacid decreased. Polymers containing a few I- p showed an increase in the initial modulus.

A series of six photo-crosslinkable thermotropic liquid crystalline copolyesters were prepared by polycondensation method at room temperature using tetra-n-butylammonium bromide as the phase transfer catalyst. The diacid chloride involved in this process was adipoyl chloride, the common diol (diol-1), also referred to as bischalcone diol, used was 3,3′-benzene-1,4-diylbis[1-(4-hydroxyphenyl)prop-2-en-1-one] and six different arylidene diols were involved as varying diols (diol-2), in the ratio 2:1:1. The common diol and the six arylidene diols were synthesized by the acid-catalyzed Claisen-Schmidt synthesis. The inherent viscosity ηinh of these six copolyesters was found between 0.35 and 0.45. The microstructure of the repeating unit present in the copolyester chain was confirmed by FT-IR, 1H–NMR and 13C–NMR spectroscopic techniques. Thermal transition temperatures, resolved from the DSC thermograms, were found to be well above room temperature. Optical polarizing microscopy was employed to establish the liquid crystalline property and all the polymers were found to have nematic phase. The photo-crosslinking behaviour of these copolyesters was studied in DMF solution at different time intervals. The copolyesters having methoxy group in them absorb UV-A rays (315–400 nm) for a longer duration, which promotes them to be good candidates for UV filters and sunscreens.

In attempt to prepare modified ultrafiltration (UF) Nylon 6 membrane and improve its hydrophilicity and anti-fouling performance, poly (acrylamide-co-maleic anhydride)(AM-MA) was utilized as hydrophilic copolymer additive in the dope solution. The UF Nylon 6/AM-MA membranes were synthesized through blending Nylon 6 with poly(AM-MA) using a phase inversion process. Characterization of the prepared membranes for morphological studies and thermal behavior was carried out by SEM and DSC instruments respectively. The SEM photos demonstrated that by increasing the copolymer density in the dope solution, the morphology was changed from spongy to bi-continuous, composed of small interlocked and stick-like crystallites. FTIR/ATR and water contact angle data also confirmed the existence of AM-MA copolymer on the blend membranes surface. Furthermore, the effect of different molecular weights and concentration of hydrophilic copolymer on filtration performance and antifouling properties were experimentally studied. The results exhibited that the blend UF membranes possessed better water flux permeability than pure Nylon 6 membrane due to the increased surface hydrophilicity and porosity. Fouling resistance experiments revealed that the surface anti-fouling ability of the blend membranes was improved via the addition of AM-MA copolymer with lower MW (co1) to the cast solution, while this parameter was weakened in higher MW of copolymer (co2).

In this study, we report a simple method which via modified-colloid silica blending with polybutadiene-base polyurethane to form a hydrophobic composite material. The hydrophobic film is characterized by optical microscopy, scanning electron microscopy (SEM), and water contact angle. Desired surface roughness was obtained by hydrophobic silica tuning the microstructures that contact angle approach 150.1o when contain ODTMS/colloid silica =90/10. With the increase of the blended ratio of modified silica with the PBU, we also could obtain the rough surface, and increased its hydrophobicity.

The crystallization of trans-1,4-polyisoprene (TPI) was influenced by many factors, such as the processing temperature, pressure and stress. The crystallization of TPI prepared under different conditions (temperature, pressure and tension) was characterized by Fourier transform infrared spectroscopy (FTIR), polarizing light microscopy(POM)and X-ray diffraction(XRD). The experimental results showed that the absorption frequency and the intensity of the FTIR spectra were not influenced by Mooney viscosity of TPI, however, it deeply affected by the sample preparation methods. The spectrum of hot pressed films showed a combination of α-form and β-form crystals, while that of solution cast films showed the characteristic absorption bands of α-form crystals and less β-form crystals. Spherulites of TPI could be obtained at several different crystallization temperatures (45 °C, 18 °C and 9 °C), but the size of the spherulites decreased from ~180 μm to ~70 μm with the decrease of temperature from 45 °C and 9 °C. When the temperature of the specimen decreased at a uniform rate (1.5 °C/min), large size spherulites were obtained. With the increase of pressure, the spherulites were not perfect. XRD patterns of TPI revealed that both α-form and β-form crystals existed in stretched specimens. Part of the α-form crystals transformed into β-form crystals during the extension.

Synthesis of poly(styrene-b-methyl methacrylate) block copolymers were obtained via reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene using RAFT-macro agent. For this purpose, 4-bromomethyl benzoyl chloride was obtained using 4-methylbenzoyl chloride and N-bromosuccinimide. The mono functional bromomethyl benzoyl t-butyl peroxy ester (t-BuBP) was obtained by reaction of 4-bromomethyl benzoyl chloride with t-butyl hydroperoxide. Terminally brominated poly(methyl methacrylate) (PMMA-Br) was synthesized using t-BuBP and methyl methacrylate via free-radical polymerization. RAFT-macro agent was acquired by reaction of PMMA-Br and potassium ethyl xanthogenate. By reacting RAFT-macro agent and styrene, block copolymers were obtained. The primary parameters, for example concentration, and time that affect reaction were evaluated. The products were characterized by FT-IR, 1H-NMR, GPC, and TGA. The multi instruments studies of the obtained block copolymers show that the copolymers easily formed as a result of RAFT. Mn,GPC values of the copolymers were between 24,900 g.mol−1 and 74,100 g.mol−1.

Photochromic materials with stable properties during long-term use have a very broad application prospect. Herein, five kinds of spirooxazines (SO1-SO5) with antioxidant properties were successfully synthesized by blending and covalently bonding antioxidants. Then various photochromic polyacrylate laminating adhesives (PA1-PA7) with good fatigue resistance were prepared by incorporating spirooxazines into polyacrylate. Among them, this study used 2, 6 -di-tert-butyl-4-methylphenol (BHT) as the main antioxidant, and tris (2, 4-di-tert-butylphenyl) phosphite (168) as the auxiliary antioxidant. Upon ultraviolet (UV) activation, these PA films possessed superior photochromism and light responsiveness. Importantly, unlike traditional physical blending photochromic polymers, SO2 was successfully covalently bonded into PA through reaction (PA6), effectively improving the fatigue resistance and thermal stability of the PA film. Doping with BHT, it further improved the photochromic properties of the compound film (PA7).

In this work, chitin flakes were deacetylated with 50% (w/v) sodium hydroxide under nitrogen atmosphere at 120 °C for 80 min to obtain chitosan. The chitosan produced was characterized for degree of deacetylation (DD) and molecular weight. Chitosan with the DD of 78–80% was reproducibly obtained. Molecular weight showed an inverse relationship with concentration of NaOH. Chitosan nanofibrous membrane was prepared via the electrospinning of chitosan/polyvinyl alcohol (CH/PVA) aqueous solutions with varying blend compositions. The characteristics of CH/PVA nanofibrous membranes were studied as a function of viscosity of solution and applied voltage. A uniform nanofibrous membrane of average fibre diameter of 80–300 nm was obtained with blend of 2% (w/v) chitosan solution in 1% (v/v) acetic acid and 5% (w/v) PVA in distilled water in the electric field of 20–25 kV with varying proportion of CH/PVA. With the CH/PVA mass ratios; 40/60 to 10/90, electrospinning of nanofibres could be done. The electrospun nanofibrous membrane was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Thermo gravimetric analysis (TGA). SEM images showed that the morphology and diameter of the nanofibres were mainly affected by the weight ratio of CH/PVA. XRD and FTIR confirmed the strong intermolecular hydrogen bonding between the molecules of Chitosan and PVA.