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In order to prevent freshwater biofouling glass and metal surfaces were coated with novel transparent methacrylate-based copolymers. The multifunctionality of the copolymers, such as adhesion to the substrate, surface polarity, mechanical long-term stability in water, and ability to form metal complexes was inserted by the choice of suitable comonomers. The monomer 2-acetoacetoxy ethyl methacrylate (AAMA) was used as complexing unit to produce copper(II) complexes in the coating’s upper surface layer. The semifluorinated monomer 1H,1H,2H,2H- perfluorodecyl methacrylate was employed to adjust the surface polarity and wettability. Comprehensive surface characterization techniques, such as X-ray photoelectron spectroscopy (XPS) and contact angle measurements showed that surface compositions and properties can be easily adjusted by varying the concentrations of the comonomers. The formation of copper(II) complexes along the copolymer chains and their stability against washing out with plenty of water was proven by XPS. Copolymers containing semifluorinated comonomers significantly inhibited the growth of Achnanthidium species. Copolymers with copper-loaded AAMA-sequences were able to reduce both the growth of Achnanthidium spec. and Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

We present a detailed structural characterization of 6-[4-(4´-cyanophenyl)phenoxy]hexyl methacrylate (CPPHMA) side chain liquid crystal homopolymer and its copolymers with either 4-benzoylphenyl methacrylate (BPMA) or methyl methacylate (MMA) and BPMA. The thermotropic properties of copolymers with stepwise varied chemical composition are investigated with differential scanning calorimetry (DSC) and polarized optical microscopy (POM). Two-dimensional and temperature-dependent X-ray scattering measurements are employed to determine the liquid crystalline phase behavior and to elucidate the copolymer microstructure. While the P(CPPHMA) homopolymer exhibits a smectic A phase, copolymers having CPPHMA comonomer content of 79 mol% and higher show weak liquid crystalline behavior. Structural models are proposed for the layered smectic phase of the homopolymer and the copolymers on the basis of the results of the X-ray measurements. [ABSTRACT FROM AUTHOR]

Comb-like copolymers based on a polyolefin backbone of poly(10-undecene-1-ol) (PUol) with poly(ε-caprolactone) (PCL) side chains are synthesized in two steps. After synthesis of PUol by metallocene-catalyzed polymerization, the side-chain hydroxyl functionalities of this polar polyolefin are used as an initiator for the ring-opening polymerization (ROP) of ε-caprolactone (CL). In this context, copolymers with different lengths of PCL grafts are prepared. The chemical structure and the composition of the synthesized copolymers are characterized by 1H and 13C NMR spectroscopy. It is shown that the hydroxyl end groups of PUol act effectively as initiating sites for the CL ROP. Size-exclusion chromatography (SEC) measurements confirm the absence of non-attached PCL and the expected increase in molar mass after grafting. The thermal and decomposition behaviors are investigated by DSC and thermogravimetric analysis (TGA). The effect of the length of the PCL grafts on the crystallization behavior of the comb-like copolymers is investigated by DSC and wide-angle X-ray scattering (WAXS). [ABSTRACT FROM AUTHOR]

Flame retarded poly(butylene terephthalate) (PBT) is required for electronic applications and is mostly achieved by low molar mass additives so far. Three phosphorus-containing polyesters are suggested as halogen-free and polymeric flame retardants for PBT. Flame retardancy was achieved according to cone calorimeter experiments showing that the peak heat release rate and total heat evolved were reduced because of flame inhibition and condensed-phase activity. The presented polymers containing derivatives of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide form immiscible blend systems with PBT. Shear-rheology shows an increase in storage moduli at low frequencies. This is proposed as quantitative measure for the degree of phase interaction. The phase structure of the blends depends on the chemical structure of the phosphorus polyester and was quite different, depending also on the viscosity ratio between matrix and second phase. A lower viscosity ratio leads to two types of phases with spherical and additionally continuous droplets. Addition of the flame retardants showed no influence on the dielectric properties but on the mechanical behavior. The polymeric flame retardants significantly diminish the impact strength because of several reasons: (1) high brittleness of the phosphorus polyesters themselves, (2) thermodynamic immiscibility, and (3) weak phase adhesion. By adding a copolymer consisting of the two base polymers to the blend, an improvement of impact strength was obtained. The copolymer particularly acts as compatibilizer between the phases and therefore leads to a smaller phase size and to a stronger phase adhesion due to the formation of fibrils. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

As a method of compatibilization of immiscible polyether ether ketone (PEEK)/polysulfone (PSU) blends, the addition of segmented PEEK/PSU block copolymers based on amorphous bisphenol A-containing PEEK was studied. This approach was evaluated for blends consisting of PEEK and PSU homopolymers with different molecular weights and different amounts of compatibilizers (segmented PEEK/PSU block copolymers and reactive end-functionalized PEEK and PSU oligomers). The compatibilizers were added under varying melt-processing conditions and effectively allowed the homopolymers to interact with the segmented block copolymers in the blend. The influence of the compatibilizers on the phase behavior was examined in both binary and ternary blends. Interactions in the amorphous phase, which effectively induce an enhancement of the toughness properties of the final product, could be detected. [ABSTRACT FROM AUTHOR]

Abstract: The direct copolymerization of propene with polar comonomers using metallocene catalysts in solution was investigated. As comonomers, two ether compounds were used in comparison to 10-undecene-1-ol as well-investigated comonomer. The ether comonomers were diethylene glycol mono-10-undecenyl ether (DEGUE) and octaethylene glycol-10-undecenyl methyl ether (OEGUME). The influence of the different comonomers on the copolymerization behavior was studied. The copolymers were characterized with respect to their comonomer contents, molar masses, and thermal properties. The incorporation rate of DEGUE and OEGUME into the propene copolymers did not exceed 1.6mol% for DEGUE and 0.31mol% for OEGUME and was thus considerably lower than in the reference propene copolymerization with 10-undecene-1-ol. An uncompleted shielding of the oxygen atoms of the ether groups by triisobutyl aluminum (TIBA) to the metallocene catalyst is assumed to be responsible for this behavior. The crystallization kinetics in the copolymers with comparable molar masses is mainly influenced by the side chain density per 1000 propene units, n 1000. The incorporation of hydrophilic comonomers into polypropene was expected to alter the surface properties. The slightly lowered water contact angles found on films of copolymers with higher comonomer content indicated the enhanced hydrophilicity of the polypropene copolymer surfaces compared to polypropene (PP). [Copyright &y& Elsevier]

Semifluorinated (SF) side chain polymers show phase separation between polymer backbone and SF side chains. Due to strong interaction between SF segments the side chains determine the structure behaviour strongly, often resulting in layered structures in which backbones and layers of SF side chains alternate. The interest in this work was directed to find out the dependence of these structures on concentration of SF side chains. Thin films of random copolymers consisting of methylmethacrylate (MMA) and semifluorinated side chain methacrylate (SFMA) segments and with different fluorine content in the perfluoroalkyl side chains (abbreviated as H10F10 and H2F8) were prepared by spin-coating. Phase separation and structure changes were initiated by external subsequent annealing. Corresponding bulk material served as basic information. Generation of ordered structures and variation of film parameters were observed using different X-ray scattering methods (XRR, GIWAXS, and GISAXS). The phase behaviour in bulk is governed by the SF side chain amount and their specific fluorine content which control the self-organization tendency of SF side chains. Additionally, the confinement in thin films generates an orientation of side chains normally to film surface. [ABSTRACT FROM PUBLISHER]

The synthesis of novel phosphonate-containing copolymers with methyl methacrylate (MMA) is reported. As phosphonate comonomers ethyl-2-[4-(dihydroxyphosphoryl)-2-oxabutyl]acrylate (EDHPOBA), with free phosphonic acid group, and the respective methyl ester ethyl-2-[4-(dimethoxyphosphoryl)-2-oxabutyl]acrylate (EDMPOBA) are employed. The impact of the phosphonate-containing comonomers on the thermal decomposition of P(MMA) copolymers is discussed using data obtained from thermogravimetric analysis (TGA). P(MMA) decomposes completely under nitrogen leading to a negligible residue, while the decomposition of copolymers containing the phosphonate comonomer EDHPOBA yields a significant residue (up to 32 wt.%) indicating a significant alteration of the decomposition mechanism. TGA/FTIR experiments are performed to determine the volatile decomposition products of the copolymers. It is demonstrated that incorporation of the phosphonic acid-containing monomer in P(MMA) suppresses the depolymerization of P(MMA) Alternative pyrolysis reactions take place and MMA is not detected in the gas phase. The decomposition proceeds essentially in four steps: transesterification between acrylate ester groups and phosphonic acid, anhydride formation, decarboxylation, McLafferty rearrangement and cyclization (char forming). It is found that this reaction sequence cannot occur in copolymers with the ester EDMPOBA comonomer, thus resulting in a less favored influence on the decomposition mechanism. Microscale combustion calorimetric measurements prove that incorporation of the phosphonate monomers drastically reduces the total heat release and heat release capacity. [ABSTRACT FROM AUTHOR]

UV-Crosslinkable itaconic copolymers are developed to provide new multifunctional materials for coatings which combine crosslinkable functionalities and the possibility to immobilize enzymes. The polymer-immobilized enzymes were used for water treatment to decompose persistent organic molecules. Introduction of suitable comonomers allows tailoring the mechanical and chemical properties for special applications. Copolymers containing MMA and itaconic anhydride were chosen because of the formation of long-term stable anhydride functionalities. These anhydride functionalities are employed to attach enzymes covalently. 4-Benzoylphenyl methacrylate is used as comonomer for UV-initiated crosslinking. Terpolymers are successfully obtained by radical copolymerization in solution. The copolymers are compared to poly(ethylene- alt -maleic anhydride) [P(EMA)] often used with respect to enzyme immobilization, activity and hydrolytic stability. The hydrolysis stability of the copolymers against water is studied by ATR-FTIR spectroscopy. Thin films are prepared on glass substrates in a layer-by-layer procedure by spin-coating. The layer formation is monitored by ATR-FTIR spectroscopy. UV-crosslinking of the copolymer films is performed taking the optimal irradiation dose that avoids polymer degradation. ATR-FTIR spectroscopy verifies the coupling reaction between amino groups of the enzyme and the anhydride groups on the surface of the crosslinked polymer film. The syringaldazine (4-hydroxy-3,5-dimethoxybenzaldehyde azine) test and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay demonstrate that the immobilized enzymes maintain their activities. The functional copolymers showed a significant effect in reduction of persistent organic pollutants in contaminated waste water. [ABSTRACT FROM AUTHOR]