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We report the preparation, mechanisms and thermal properties of core-shell structured polymer/inorganic nanoparticle composite microspheres prepared by Pickering emulsion polymerization. Stable Pickering emulsion was firstly fabricated by using surface-modified nano-SiO2 particles as stabilizer. And then, two kinds of polystyrene/nano-SiO2 (PS/SiO2) composite microspheres with different sizes and morphologies were synthesized using hydrophobic azobisisobu- tyronitrile (AIBN) and hydrophilic ammonium persulfate (APS) as initiator, respectively. The possible mechanisms of Pickering emulsion polymerization initiated by different initiators were proposed according to the results of transmission electron microscope (TEM) and scanning electron microscope (SEM). The chemical structure and molecular weight of the composite microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and gel permeation chromatography coupled with a multi-angle laser light scattering photometer (GPC-MALLS). Thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) were used to comparatively analyze the thermal properties of nanocomposites and corresponding pure polymer. The results indicated that the decomposition tem- perature and glass transition temperature (Tg) of nanocomposites were elevated to a certain degree due to the existence of nano-SiO2.

In order to enhance the adhesion between inorganic particles and polymer matrix, in this paper, the mesoporous silica SBA-15 material was synthesized by the sol-gel method. The surface of SBA-15 was modified using γ-glycidyloxypropyltrimethoxysilane (GOTMS) as a coupling agent, and then mesoporous silica/phenolic resin (SBA-15/PF) nanocomposites were prepared via in situ polymerization. The structural parameters and physical properties of SBA-15, SBA-15-GOTMS (SBA-15 surface treated using GOTMS as coupling agents) and E-SBA-15/PF (SBA-15/PF nanocomposites extracted using ethanol as solvent) were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The thermal properties of the nanocomposites were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results demonstrated that the GOTMS were successfully grafted onto the surface of SBA-15, and chemical bonds between PF and SBA-15-GOTMS were formed after in situ polymerization. In addition, it is found that the in situ polymerization method has great effects on the textural parameters of SBA-15. The results also showed that the glass transition temperatures and thermal stability of the PF nanocomposites were obviously enhanced as compared with the pure PF at silica contents between 1–3 wt%, due to the uniform dispersion of the modified SBA-15 in the matrix.

Thermal stability of hybrid composites prepared from epoxy, novolac, and epoxidized-novolac resins and also modified graphene oxide (SFGO) was studied. SFGO was prepared by covering graphene oxide with silica nanoparticles and a bifunctional silane modifier. The first hybrid was prepared from SFGO and silane-modified epoxy resin. The second one was prepared from SFGO, and silane-modified epoxy and novolac resins. The third hybrid was formed from SFGO, silane-modified novolac, and epoxidized novolac resins. Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) results showed that modification of graphene oxide was carried out successfully. TGA results show that degradation temperature and char residue of resins were increased through their incorporation into hybrid network with SFGO. In addition, the most increase of char residue was observed for the hybrid composites formed from SFGO and modified novolac and epoxy resins.

Epoxidized soybean oil (ESO) was successfully thermal-cured by using methylhexahydrophthalic anhydride (MHHPA) curing agent, in the presence of tetraethylammonium bromide (TEAB) catalyst of varied concentration (0.3-0.8 phr). The polyesterification process of ESO thermoset was proven and supported by Fourier transforms infrared spec- troscopy (FTIR) and gas chromatography-mass spectroscopy analysis (GC-MS). A possible chemical reaction of the MHHPA, TEAB and ESO was proposed based on the experimental work. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) revealed that there is a positive relationship between the degree of conversion and crosslink density of ESO thermoset with TEAB concentration. The kinetics of water absorption of the ESO thermoset were found to conform to Fickian law behavior.

Poly (St-MAn-APTES)/silica hybrid materials were successfully prepared from styrene (St), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of a coupling agent 3-aminopropyltriethoxysilane (APTES), by free- radical solution polymerization and in situ sol-gel process. The TEOS content varied from 0 to 25 wt%. Fourier transform infrared spectroscopy and 29 Si nuclear magnetic resonance spectroscopy were used to characterize the structure of the hybrids (condensed siloxane bonds designated as Q1, Q2, Q3, Q4, with 3-aminopropyltriethoxysilane having mono-, di-, tri, tetra-substituted siloxane bonds designated as T1, T2 and T3). The results revealed that Q3, Q4 and T3 were the major microstructure elements in forming a network structure. The hybrid materials were also characterized by the methods of solvent extraction, Transmission Electron Microscopy (TEM), differential scanning calorimetry (DSC) and thermogravi- metric analysis (TGA) for determining the gel contents, particle size and thermal performance. The results showed that gel contents in the hybrid materials were much higher, the SiO2 phase were well dispersed in the polymer matrix, silicon diox- ide existed at nanoscale in the composites, which had excellent thermal stability.

A racemic mixture of two stereoregular polylactides (PLAs) (i.e. PLLA and PDLA) allows obtaining wholly amorphous stereocomplex PLA films by solvent casting method. The amorphous phase behavior of stereocomplex PLA is compared with that of PLLA and PDLA by advanced thermal analysis, such as Fast Scanning Calorimetry (FSC) and Dielectric Relaxation Spectroscopy (DRS). FSC allows us to quench at very high cooling rate (up to 4000 K・s–1) the studied polymers and to obtain glassy amorphous phases with high excess of enthalpy. It is shown that stereocomplexation has no influence on the glass transition temperature, the physical aging and on the cooperativity. The α and β processes were examined to study the dielectric properties, such as relaxation time, dielectric strength, and fragility. The results of FSC and DRS are correlated to determine the values of cooperativity length which are found to be similar in a wide temperature range. It is found that the studied polymers have the similar dielectric properties independently on their tacticity.

In the current manuscript, a new approach for the synthesis of poly(1,4- cyclohexanedimethylene 2,6-naphthalate) (PCHDMN) derived from dimethyl 2,6-naphthalenedicarboxylate (2,6-DMN) and 1,4-Cyclohexanedimethanol (CHDM) via melt polycondensation method is introduced. The effect of three different synthesis pathways, polycondensation time and temperature on polyesters molecular weight increase has been investigated. All of the prepared samples were characterized measuring their intrinsic viscosity (IV), thermal properties and morphology with differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD), respectively. The results demonstrated the effectiveness of the synthesis pathway proposed for the preparation of PCHDMN, resulting in high molecular weight (IV value around 0.5 dL/g) and much shorter reaction time. Melt polycondensation temperatures above melting point of polyester should be avoided to be used due to the decomposition of polyester. This was proved by thermogravimetric analysis (TGA) and Pyrolysis-gas chromatography–mass spectroscopy analysis (Py-GC/MS).

Novel tough bio-based polyesters poly(ethylene 2,5-thiophenedicarboxylate-co-1,4-cyclohexanedimethylene 2,5-thiophenedicarboxylate)s (PECTFs) were synthesized from 2,5-thiophenedicarboxylic acid (TDCA), 1,4-cyclohexanedimethanol (CHDM) and ethylene glycol (EG). The microstructure, thermal and mechanical properties were investigated. Poly(ethylene 2,5-thiophenedicarboxylate) (PETF) displayed the glass transition temperature (~64 °C) and tensile strength (~72 MPa) similar to poly(ethylene terephthalate) (PET). However, the nonlinear structure of TDCA resulted in an angle of 148° between carboxylic acid carbons and the S atom resulted in a permanent dipole, so the thiophene ring-flipping was hindered and the low elongation at break (~24%) was observed for PETF. The peak corresponding to the secondary relaxation shifted to lower temperature due to the incorporation of CHDM, which yielded ductile copolyesters with high elongation at break. When the CHDM content was equal to or higher than 29%, a high elongation at break (>160%) was observed.

A stable and reproducible bi-component melt spinning process on an industrial scale incorporating Phase Change Material (PCM) into textile fibres has been successfully developed and carried out using a melt spinning machine. The key factor for a successful bi-component melt spinning process is that a deep insight into the thermal and rheological behaviour of PCM using Difference Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and an oscillatory rheological investigation. PCM is very sensitive to the temperature and residence time of the melt spinning process. It is found that the optimal process temperature of PCM is 210 °C. The textile-physical properties and the morphology of the melt spun and further drawn bi-component core and sheath fibres (bico fibres) were investigated and interpreted. The heat capacities of PCM incorporated in bico fibres were also determined by means of DSC. The melt spun bico fibres integrating PCM provide a high latent heat of up to 22 J/g, which is three times higher than that of state-of-the-art fibres, which were also obtained using the melt spinning process. Therefore, they have the potential to be used as smart polymer fibres for textile and other technical applications.

Poly(trimethylene 2,5-furanoate) (PTF) nanocomposites reinforced with few layer graphene (FLG) were prepared through in situ polymerization. The method in question allows obtaining well-dispersed nanoplatelets in the whole volume of PTF matrix. The mechanical properties of the PTF/FLG nanocomposites slightly increased with as quantity of FLG as small as 0.1 wt%, which was best seen in the improvement of elongation at break by about two times. The presence of FLG did not affect the crystallization and chain mobility of PTF matrix. However, the incorporation of a small quantity of FLG slightly improved the thermal stability of the nanocomposites. Additionally, the cold and hot water absorption and oxygen permittivity measurements confirmed that FLG affected the tortuosity of the diffusive path for the penetrant molecule. Moreover, along with a successive addition of FLG a linear increase in thermal conductivity was visible.

Binary blends composed of 1,3-bis (3,4-dicyanophenoxy) benzene (3BOCN) and ionic liquids (ILs) with different molecular structures were prepared. The curing behavior of these 3BOCN/ILs blends were studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and rheological analysis. The study suggested that the blends possessed a wide processing window and the structures of ILs (anion, cation and alkyl chain length at cation) had an effect on curing behavior. The 3BOCN/[EPy]BF4 resins were prepared at elevated temperature. IR spectra of the resins showed that there were triazine and isoindoline formed in curing process. The TGA and dynamic mechanical analysis (DMA) revealed that the resins have excellent thermal stability together with high storage modulus and high glass transition temperature (Tg). Dielectric properties, long term oxidative aging and water uptake measurements of the resins suggested the IL brought some unique properties to the resins.

A new bio-based elastomer, poly(butylene 2,5-furandicarboxylate-ε-caprolactone) (PBFCL), has been synthesized from 2,5-furandicarboxylic acid, 1,4-butanediol, and ε-caprolactone successfully for the first time. The obtained copolyester was characterized in terms of chemical structure, thermal and mechanical properties, and enzymatic degradability. In PBFCL elastomer, butylene-2,5-furandiacrboxylate units (hard segments) crystallize to serve as physical crosslinks while ε-caprolactone polyester diol (soft segments) provide flexibility. PBFCL is a multi-blocked copolyester with randomly distributed rigid and soft segments. It possesses original feature of high strength and biodegradability stemming from the uses of aromatic and aliphatic monomers respectively. An important aspect of this new furanic-aliphatic polyester is its tailor-made properties simply achieved by changing the content of hard or soft segments. Typically, PBFCL-40 of optimal composition has Young’s modulus as low as 15.4 MPa, tensile strength as high 24.8 MPa, and elongation as long as 885%.

A polyimide (PI) aerogel with excellent combined thermal and dielectric properties was successfully prepared by the polycondensation of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 5-amino-2-(4-aminophenyl)benzoxazole (APBO) and octa(amino-phenyl)silsesquioxane (OAPS) crosslinker, followed by a supercritical carbon dioxide (scCO2) drying treatment. The developed PI aerogel exhibited an ultra-low dielectric constant (k) of 1.15 at a frequency of 2.75 GHz, a volume resistivity of 5.45·10 14 Ω·cm, and a dielectric strength of 132 kV/cm. The flexible PI aerogel exhibited an open- pore microstructure consisting of three-dimensional network with tangled nanofibers morphology with a porosity of 85.6% (volume ratio), an average pore diameter of 19.2 nm, and a Brunauer-Emmet-Teller (BET) surface area of 428.6 m 2 /g. In addition, the PI aerogel showed excellent thermal stability with a glass transition temperature (Tg) of 358.3 °C, a 5% weight loss temperature over 500 °C, and a residual weight ratio of 66.7% at 750 °C in nitrogen.

© BME-PT. In the present study, the effect of nano magnetite (Fe3O4) content on structural, dielectric/electrical, magnetic and thermal properties of poly(vinylidene fluoride)/carbon nanotubes matrix, is investigated. Nanocomposite films of polyvinylidene fluoride, carbon nanotubes and Fe3O4nanoparticles were prepared by the twin screw compounding method. Fe3O4, as magnetic inclusions was incorporated into the composites with carbon nanotubes loadings well above the percolation threshold, where conductive networks were formed. Magnetic characterization revealed the ferrimagnetic behavior of nanocomposites, with saturation magnetization values depending on magnetite content. Results obtained from the analysis of Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques were very informative for the study of the polymorphism and crystallinity in PVDF. The incorporation of Fe3O4inclusions in PVDF/CNT matrix, gradually increase both electrical conductivity and dielectric permittivity up to 10 wt% Fe3O4content, while at the higher Fe3O4 content (15 wt%) reduced values were obtained. This behavior, at higher Fe3O4content, should be possible related to the insulating and barrier role of Fe3O4nanoparticles.

UV photo-oxidation was first applied to fabricate superhydrophobic polyimide (PI) films in combination with fluoroalkylsilane (FAS) modification. During prolonged UV irradiation, commercial flat PI films evolved to form unique micro/nanostructures. Meanwhile, the root mean square (RMS) surface roughness increased from 1.74 to 53.70 nm, leading to a gradual increase of WCA from 105.1 to 159.2° after FAS treatment. After 72 h of UV radiation exposure, the micro/nano-structured and FAS-modified PI films exhibited superhydrophobicity with water contact angle (WCA) larger than 150° and sliding angle (SA) less than 5°. The superhydrophobicity remained even after annealing at 350°C, which enabled stable utilization under elevated temperature. Stable micro/nanostructures and chemical bonding of FAS were found to contribute to the high thermal endurance. Moreover, the formation mechanism of the superhydrophobic PI films was investigated. The proposed UV photo-oxidation method provides a new route for the industrial fabrication of thermally stable superhydrophobic PI films.

nonylphenoxy-1, 2-dinitrilbenzene (NP-ph), a novel kind of phthalonitrile containing flexible hydrocarbyl chains, has been synthesized. The structures of NP-ph were investigated by Nuclear Magnetic Resonance Spectroscopy ( 1 H-NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Low viscosity NP-ph/phthalonitrile containing benzox- azine (BA-ph) blends were achieved by melt blending BA-ph with various content of NP-ph. Copolymerization behaviors and processability of NP-ph/BA-ph have been investigated by Differential Scanning Calorimetry (DSC) and Dynamic Rhe- ological Analysis. Results indicated that NP-ph/BA-ph blends processability was improved and can be controlled by vary- ing NP-ph contents, processing temperature and time. NP-ph/BA-ph polymers were prepared from the thermal polymerization with short curing time and low curing temperatures without addition of any other curing agents, which dis- played high glass transition temperature (>360°C) and attractive thermal decomposition temperature (>420°C). The out- standing glass transition temperature and desirable thermo-oxidative stabilities, together with good processability and sound process conditions could enable the NP-ph/BA-ph polymers to be further explored in the fields under some practical critical circumstances with requirements of high wears and temperatures.

Present work reports novel synthesis of Polyaniline (PANI)/Se nanocomposites. Se nanowires are prepared from SeO2 under assistance of vitamin C and polyaniline is synthesized through chemical oxidation. The effect of composition of Se nanowires on the properties of polyaniline was investigated and five orders increase in conductivity after doping has been observed. The electrical properties of nanocomposites show that conduction is through hopping process due to the wide range of localized states present near fermi level. FTIR (Fourier Transform Infrared spectroscopy) and ultraviolet (UV)-visible studies confirm the occurrence of polyaniline in conducting emeraldine salt form in the composites and sug- gest incorporation of Se in polymer. The optical studies indicate that absorption mechanism is due to indirect allowed tran- sition and the optical band gap tends to decrease after doping. The thermal stability of composites has been ascertained on the basis of DSC (Differential Scanning Calorimetery) measurements. TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy) analysis have also been carried out for morphological studies.

The object of this study was to investigate how different decreasing of pH regimes during microencapsulation process with melamine-formaldehyde (MF) resin affects the composition, morphology and thermal stability of microcap- sules containing a phase-change material (PCM). Technical butyl stearate was used as PCM. Microencapsulation was car- ried out at 70°C. For all experiments the starting pH value was 6.0. After one hour of microencapsulation at the starting pH value, the pH value was lowered to final pH value (5.5; 5.0; 4.5) in a stepwise or linear way. The properties of microcap- sules were monitored during and after the microencapsulation process. The results showed that pH value decreasing regime was critical for the morphology and stability of microcapsules. During microencapsulations with a stepwise decrease of pH value we observed faster increase of the amount of MF resin in the microencapsulation product compared to the microen- capsulations with a linear pH value decrease. However, faster deposition in the case of microencapsulations with stepwise decrease of pH value did not result in thicker MF shells. The shell thickness increased much faster when the pH value was decreased in a linear way or in several smaller steps. It was shown that for the best thermal stability of microcapsules, the pH value during microencapsulation had to be lowered in a linear way or in smaller steps to 5.0 or lower.

The encapsulation of octadecane (OD) as heat storage material was studied. The core-shell polydivinylbenzene (PDVB)/natural rubber (NR) capsules encapsulating OD was prepared using the Self-assembling of Phase Separated Poly- mer (SaPSeP) method by suspension polymerization. The mixture of dispersed phase consisting of DVB, NR, OD and ben- zoyl peroxide was added in polyvinyl alcohol aqueous solution and then homogenized at 5,000 rpm for 5 minutes. The obtained monomer droplet emulsion was subsequently polymerized at 80°C for 8 hours resulting in PDVB/NR capsule encapsulating OD. The influence of molecular weight and content of NR on the encapsulation efficiency and thermal prop- erties of the encapsulated OD were investigated. It was found that both factors affected on the preparation of PDVB/ NR/OD capsule. High molecular weight NR restricted phase separation of formed PDVB. High NR content also reduced phase separation of PDVB due to the increase of internal viscosity. Then, only the incorporation of appropriate molecular weight and content of NR resulted in the formation of PDVB/NR/OD capsule.

Recycling of waste poly(ethylene terephthalate) (PET) has attracted much attention in recent years because of the pressure from the environment. However, the cost-effective conversion of waste PET into value-added products by ecofriendly methods remains to be a challenge in the industry. In this work, a method for converting PET into calcium terephthalate by reactive melt processing was developed and investigated. Specifically, PET pellets were blended with calcium hydroxide powders using reactive melt processing, and the resulting mixture was converted into calcium terephthalate by simple hydrolysis in water. Physicochemical characterizations for morphologies, chemical compositions, and thermal properties were conducted to investigate intermediate components produced during the process, as well as the mechanisms of this new process. The results indicate that the effective transformation of molten PET into calcium terephthalate may be attributed to several factors, including the strong mechanical interaction during melt mixing, the thermal decomposition of PET chains to form carboxylic end groups, and the catalytic nature of calcium hydroxide in PET hydrolysis. This research can lead to a cost-effective route for the upcycling of waste PET into a value-added product that may be useful in demanding and emerging applications.

In this study, well-dispersed nanocomposite films with triacetate cellulose (TAC) as a matrix and reinforced with lemon peel-cellulose nanofibers (lemon peel-CNF) were developed. The nanofibers in aqueous solution were solvent-exchanged to methanol by a series of centrifuging and re-dispersing steps. Afterward, using the solution casting method, the mixture of recycled TAC (rTAC) film and nanofibers prepared by stirring combined with ball milling technique to achieve full dispersed solution was coated onto glass to obtain a thin film. The dispersion effect of CNF in TAC was observed by transmission electron microscopy. The optical, mechanical, and thermal properties of the nanocomposite films were characterized experimentally. The results showed that with varying CNF content (1–7 wt%), the haze was slightly increased while the transmittance was not affected compared with that of rTAC film (92.7%). The addition of CNF increased the tensile strength by 60%, tensile strain by 150%, and yield strength by 50%. Creep compliance improved for all nanocomposites compared with rTAC film. CNF led to a significant reduction in the thermal expansion properties of rTAC film.

In the present work, cellulose nanocrystals (CNC) and graphene nanoplatelets (GR) were combined in two different ratios and incorporated into polylactic acid (PLA) by melt blending technique, at a total loading level of 1 wt%. The obtained PLA-CNC/GR nanocomposites were further processed by hot pressing for manufacturing films. For comparison purposes, PLA-CNC, PLA-GR and PLA-T (PLA blended with the organic surfactant Triton X-100) compositions were also prepared following the same procedure. The produced materials were characterized by several techniques, including Field-Emission Scanning Electron Microscopy (FE-SEM). The mechanical properties assessment showed an increase of 8 and 11% in the Young’s modulus and tensile strength respectively for PLA- CNC/GR (ratio 50/50) film compared to PLA-T. The thermal properties were also positively influenced by the incorporation of both nanofillers. Similarly, the gas barrier properties were improved by 23% in Oxygen Transmission Rate (OTR) for films containing simultaneously CNC and GR. Finally, the antifungal properties were evaluated against Aspergillus Niger finding a superior antifungal activity in the CNC/GR hybrid films. The incorporation of CNC and GR in PLA showed a favourable impact in the overall properties of the obtained materials with only 1 wt% of nanofiller content. These results suggest that CNC/GR hybrid nanocomposites have a considerable potential in agricultural films or in food packaging trays applications.

Low molecular weight polyesters were end-functionalized with ammonium and carboxylate salts and used in ionic exchange reactions with respectively cationic (MMT) and anionic (LDH) clays. The hybrid organic-inorganic substrates were structurally analysed to determine the ester oligomers’ modification degree and their thermal behaviour owing to confinement effects. The dispersion of such hybrids in polylactic acid (PLA) matrix was performed and the ultimate structural, morphological and thermal properties of the collected nanocomposites were investigated and correlated to the tailored interfacial properties with the different inorganic substrates. While the composites with MMT proved to be stable under thermo-oxidative conditions, the samples obtained by dispersing the LDH hybrid suffered from poor final thermostability owing to molecular weights decrease. Deeper insights about the effect of the interactions at interface (polymer chain-surfactant and polymer chain- inorganic surface) evidenced that by promoting an intimate contact between PLA chains and LDH surface (through oligoester used as inorganic substrate modifier) a certain extent of PLA hydrolysis triggered by both surfactant and inorganic surface (LDH) occurred and cannot completely avoided.

A new and convenient route to the regiocontrolled synthesis of a cellulose-based derivate copolymer (2,3-di-O-polycaprolactone-cellulose) grafting ε-caprolactone (ε-CL) from α-cellulose, cellulose-graft-polycaprolactone (cellulose-g-PCL), by a classical ring-opening polymerization (ROP) reaction, using stannous octoate (Sn(Oct)2) as catalyst, in 68% concentration of zinc chloride aqueous solution at 120 °C was presented. By controlling the hydroxyl of cellulose/ε-CL, catalyst/monomer ratio and the reaction time, the molecular architecture of the copolymers can be altered. The solubility of cellulose in zinc chloride aqueous was indicated by UV/VIS spectrometer and rheological measurements. The structures and thermal properties of cellulose-g-polycaprolactone copolymers were characterized using Fourier Transform Infrared (FT-IR), Proton Nuclear Magnetic Resonance Spectroscopy (1H NMR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The interesting results confirm that zinc chloride solution can break the intra-molecular hydrogen bonds of cellulose selectively (not only O3H···O5, but also O2H···O6), and has no effect on the inter-molecular hydrogen bonds (O6H···O3). And the grafting reactivity of hydroxyl on cellulose is C2–OH > C3–OH >> C6–OH in zinc chloride solution, and this is clearly different from other researches. Most importantly, this work confirms that the method to regiocontrolled synthesis cellulose-based derivative polymers by regiobreaking hydrogen bonds is feasible. It is strongly believed that the new discovery may give a novel, environmental, simple and inexpensive method to modify cellulose chemically with various side chains grafted on a given hydroxyl, through liberating hydroxyl as reactive group from hydrogen bonds broken selectively by different solvents.

Novel epoxy-benzoxazine emulsions designed for water-based coatings were prepared and investigated. Bisphe- nol#A-based epoxy resins with molar weights of 340, 377 and 1750 g/mol along with epoxidized soybean oil were emulsi- fied using mono- and bi-functional benzoxazine surfactants, which are able to react with epoxy resins at their cure temperature. The structure of synthesized surfactants carrying one or two polyether chains was confirmed using Fourier transform infrared spectroscopy, 1 H nuclear magnetic resonance and differential scanning calorimetry. Stability of emul- sions was verified by particle diameters measurements. Coatings, made directly from emulsions, were dried and cured at elevated temperature using 3,3$-dimetoxybenzidine as curing agent to ensure a highly cross-linked structure of thermoset- ting films. Curing process, thermal properties and hardness of cured films were investigated. It was found that benzoxazine molecules were well incorporated into the epoxy network upon curing, which ensures no void structure of cured copolymer and enhanced coating properties.

Hot and cold non-isothermal crystallization of copolymers having glycolide hard segments and glycolide-co- trimethylene carbonate soft segments was investigated by calorimetry, optical microscopy and synchrotron radiation exper- iments. The effect of composition and microstructural changes on thermal properties and morphology of crystallized samples was analyzed. Significant differences were found between the nucleation density of spherulites developed during cold crystallization. Crystallizations from the melt were characterized by a lamellar insertion mechanism and a broad distri- bution of crystal layer widths. By contrast, cold crystallized samples gave rise to practically constant long periods and nar- rower distributions. Soft segments with high glycolide content were more easily incorporated in the crystalline phase by decreasing the hard segment content of the sample. A significant decrease on the melting point was observed as well as a decrease of the amorphous layer thickness and an increase of the crystalline lamellar thickness when the sample was hot and cold crystallized, respectively.

Nanospheres and nanocapsules of an amphiphilic copolymer having methylated polyethylene glycol and hexadecyl lateral groups were prepared by the solvent displacement method and using confined impinging jet mixers. Degradation, thermal properties and crystalline structure were investigated by 1H NMR, DSC, optical and electron microscopy, and X-ray diffraction techniques. Interestingly, pegylated chains hydrolyzed through ester bond cleavage, whereas the more hydrophobic hexadecyl ester groups were resistant to degradation in aqueous media. The copolymer crystallized from the melt, giving rise to spherulites with a negative birefringence and domains corresponding to crystallization of the different lateral groups. Size distribution and morphology of nanocapsules and nanospheres were mainly evaluated by electron microscopy, direct observation or negative staining of samples. Nanocapsules were characterized by a stable membrane with a thickness close to 5 nm that allowed efficient encapsulation of a triglyceride oil. Triclosan was selected as an example of a hydrophobic drug to be loaded in both nanospheres and nanocapsules. The release behavior of these dosage forms was clearly different. Thus, the Burst effect was practically suppressed when using nanocapsules; in addition, these showed a sustained, controlled release over a greater time period. Antimicrobial activity of triclosan loaded nanospheres and nanocapsules was evaluated using Gram-negative and Gram-positive bacteria. The former were highly sensitive to the released triclosan whereas the latter strongly depended on the number of particles in the culture medium

Recently, the polymer-metal complexes attracted the interest of many researchers due to their valuable electric, mechanical and thermal properties and the possibilities for their use as immobilized catalysts in various processes. The use of polymer carrier allows combining the properties of the matrix with the complex-forming ability of the ligands and reveals new perspectives for the design of new materials with an interesting complex of properties. Radiation initiated grafting is a wide field of polymer chemistry with numerous potential applications of industrial interest. 4-vinylpyridine (4VP) is a monomer polymerizing under initiation by radiation. The surface modification of polymer materials by radiation grafting of this monomer provides possibilities to prepare grafted polymers. Poly-4vinylpyridine (P4VP) and its copolymers are known for their versatility of the possible applications. The copolymer materials based on P4VP are used as membranes for retention of heavy metals [1–3], carriers for immobilization of biologically active substances [4], preparation of polymer adsorbents [5], polymer metal complexes with catalytically active centers [6–9] etc. The grafted poly-4-vinylpyridine forms stable complexes with transition metal ions and ions of metals of higher valence. The presence of nitrogen containing functional groups leads to formation of metal complexes when treated with solutions of heavy metal salts. The reactions of co-ordination of