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The grafting of different methacrylates on iPP in the solid state has been studied under various reaction conditions using a radical initiation. Three peroxides and five grafting agents representing methyl‐, ethyl‐, butyl‐, ethyl hexyl‐, and dodecyl methacrylate were tested. The grafting efficiency (GE) performed in water medium (slurry) as possible heat transfer medium was compared with the GE obtained without using water. The iPP powder was first impregnated with monomer and peroxide initiator and then water solution of NaCl was added. Obtained GEs were much higher for all peroxides and monomers used when compared with GE performed without water. Quantity of grafted monomer was determined by Fourier transform infrared spectroscopy (FTIR). The products were characterized by differential scanning calorimetry (DSC) and surface energies of grafted iPP films were measured. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Polyaddition reaction of aromatic bis(2‐oxazolines) with aliphatic dicarboxylic acids, hence AA +  BB type reactions, was studied. 1,4‐Bis(2‐oxazolin‐2‐yl)benzene (TBOX) and 1,3‐bis(2‐oxazolin‐2‐yl) benzene (IBOX) as AA monomer and aliphatic dicarboxylic acids with the number of carbon atoms 4–12 as BB monomer were used. Polymerizations were thermally initiated in the range 90–250°C, in melt or in solution of high boiling aprotic solvents. The structure of the formed poly(amide esters) was proved by NMR spectroscopy. The effects of the structure of both comonomers, duration of polymerization, polymerization temperature, type of solvent, and concentration of monomers were studied. The molecular weights of the prepared polymers are in the range 2000–25,000 g/mol. Thermal properties of the prepared samples were studied, too. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new kind of antioxidant 4‐[(3‐(triethoxysilyl)propylimino)methyl]‐2,6‐di‐tert‐butylphenol consisting of an alkoxysilyl group and a 2,6‐di‐tert‐butylphenol stabilizing moiety was synthesized and tested in isotactic poly(propylene). FT‐IR, 1H‐NMR, 13C‐NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) were used for characterization of synthesized silane stabilizer. The derivative of 4‐[(3‐(triethoxysilyl)propylimino)methyl]‐2,6‐di‐tert‐butylphenol was also prepared by the condensation reaction using the sol‐gel process. Stabilizing activity of the new silane stabilizer and its condensed form was verified by chemiluminiscence and thermogravimetry measurements in oxygen atmosphere and compared with conventional 2,6‐di‐tert‐butyl‐4‐methyl‐ phenol as well as with the conventional stabilizing system based on the mixture of Irganox 1010/Irgafos168 (weight ratio of 1:2). Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The electrospinning of an ethylene vinyl acetate (EVA) copolymer with a vinyl acetate content of 28 wt.% is limited due to the solubility of the copolymer in standard laboratory conditions. Poly(lactic acid) (PLA) is a biodegradable polymer that can be electrospun easily. However, PLA has limited applicability because it is brittle. Blends of these polymers are of interest in order to obtain new types of materials with counterbalanced properties originating from both polymeric compounds. The fibers were electrospun on a water surface from a solution mixture containing various weight ratios of both polymers using a dichloromethane and acetone (70:30 v / v ) mixture as solvent. The morphologies of the prepared non-woven mats were examined by scanning electron microscopy (SEM), and the chemical composition was investigated by X-ray photoelectron spectroscopy (XPS) and by Fourier Transform Infrared Spectroscopy (FTIR). The fibers' thermal properties and stability were examined, and the mechanical properties were tested. The results showed that the strength and flexibility of the blend samples were enhanced by the presence of PLA.

Three biodegradable plastics materials, namely pure poly(l-lactide) (PLA), PLA with plasticizer triacetine (TAC) and the mixture PLA/polyhydroxybutyrate (PHB) and TAC were investigated concerning changes of physical properties due to biodegradation in compost at 58°C up to 16days. With rising time of degradation in compost, both number and weight molecular masses were decreasing progressively, but only marginal change of the polydispersity index was observed which indicates that biodegradation is not random process. FTIR spectroscopy revealed that in spite of the extensive decrease of molecular weight, no substantial change in chemical composition was found. The most significant modification of the spectra consisted in an appearing of the broad band in region 3100-3300cm -1 , which was assigned to a formation of biofilm on the sample surfaces. This effect appeared for all three materials, however, it was much more pronounced for samples containing also triacetine. Measurement of changes in crystalline portion confirmed that amorphous phase degrades substantially faster compared to crystalline part. The plasticizer triacetine is disappearing also rather fast from the sample resulting besides other effect also in a temporary increase of Tg, which at the beginning grows almost to the value typical for PLA without plasticizer but later the Tg is decreasing due to substantial changes in molecular weight. Generally during composting, the samples keep shape for up to 8days, after that time the material disintegrates to rough powder., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Low-density polyethylene (LDPE) belongs to commodity polymer materials applied in biomedical applications due to its favorable mechanical and chemical properties. The main disadvantage of LDPE in biomedical applications is low resistance to bacterial infections. An antibacterial modification of LDPE appears to be a solution to this problem. In this paper, the chitosan and chitosan/pectin multilayer was immobilized via polyacrylic acid (PAA) brushes grafted on the LDPE surface. The grafting was initiated by a low-temperature plasma treatment of the LDPE surface. Surface and adhesive properties of the samples prepared were investigated by surface analysis techniques. An antibacterial effect was confirmed by inhibition zone measurements of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The chitosan treatment of LDPE led to the highest and most clear inhibition zones (35 mm(2) for E. coli and 275 mm(2) for S. aureus)., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Novel amphiphilic copolymers on the basis of 2-oxazolines containing a free amino group were prepared. The copolymers were synthesized by the living cationic polymerization of 2-ethyl-2-oxazoline (ETOX) and 2-(4-aminophenyl)-2-oxazoline (APOX). The main goal of this work was the synthesis of water soluble polymer material with the defined number of functional groups necessary for the attachment of proteins and polysaccharides. A high concentration of free amino groups allows immobilization of various biosubstances, e.g. drugs, proteins or polysaccharides. Thermal properties have been studied with respect to the composition of the copolymers. Cytotoxicity and the bioimmunological efficiency of the selected copolymer were studied.