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This paper presents the obtaining of some composite materials using wood waste (wood chips) and polymer. As thermoplastic matrix, a copolyamide polymer having a low melting interval (125-135°C) was used. Composites were obtained using a two-stage technology: a) wood-polymer pellets obtaining by melt mixing the components; b) composites obtaining by moulding the pellets into a heated press. The influence of wood content on composites properties was studied. Morphological details (by optical and electronic microscopy), thermal behaviour (through TGA and DSC analyses), mechanical properties (tensile, bending and impact strength) and behaviour towards water were investigated. It was concluded that, for a wood content higher than 40%, mechanical properties are getting poorer. Still, even the bending strength is decreasing, it remains 2-8 times higher than that of the composites based on polyolefinic matrix and wood chips. Keywords: composite materials, thermoplastic matrix, copolyamide polymer

The global and partial solubility parameters and radii of interaction spheres of two copolymers recommended as viscosity improvers for multi-grade mineral oils – INFINEUM SV 260 and KELTAN 4200 – were determined from solubility data and intrinsic viscosities using 13 solvents both by the classical Hansen’s method and an improved one. The obtained results are in good agreement each other and with intrinsic viscosity data. The values of the intrinsic viscosities obtained using the mineral oil SAE 10W as solvent, for which the two copolymers are intended to be used as viscosity improvers, show that it can be considered practically a very good solvent for INFINEUM SV 260 and a good one for KELTAN 4200. Keywords: multi-grade oils, viscosity improvers, global and partial solubility parameters

Liquid crystalline thermosets with biphenyl mesogen in the main chain were prepared by the curing reaction of diglycidyl ether of 4,4¢-biphenol (DGEBP) in presence of methylene-di-chloro-diethylaniline (MCDEA) and 2-amine-biphenyl (2-ABP), used as the curing agents. The product obtained by the curing reaction of DGEBP/MCDEA mixture is characterized by a texture of smectic-like structure. The curing reaction of DGEBP/2-ABP mixture led to a nematic-like structure on temperatures placed in the range of l58 - 1630C. The nematic-like texture obtained for the DGEBP/2-ABP mixture is instable at temperatures higher than 170oC. Keywords: epoxy, liquid crystal, curing, mesophase

It is known that the white organic films based on powder coatings have a large use, especially in the appliance industry; however, due to their decorative role, the colour is one of the important characteristiscs of the powder coatings. In order to obtain coloured coatings, coloured pigments, both of inorganic and organic types, have to be used to formulate powder coating compositions. They have to be selected to correspond to the end-use of the coated object, and also to be suitable for the production process for powder coatings and to the application process. The paper presents the procedure of realize the database for the ChromaCalc Paint.2. software using the DATACOLOR d200 spectrophotometer, and also the testing of the database. Keywords: organic coating, powder coating, coloured pigments

The aliphatic polyamides provide an extremely broad range of available properties for biological and medical purposes. They can be used as support in biocidal systems. The biocidal polymer coatings can contain hydantoin, imidazolidinone, isocyanurate or oxazolidinone derivatives and have considerable potential as disinfectants for general purpose. The FT-IR spectroscopy was chosen as tool in order to determine the possible changes in the structure of poly(e-caprolactam) after thermal treatment. The shifts in the frequency of absorption bands and the changes in their intensities are monitored. Keywords: poly(e-caprolactam), FT IR spectroscopy, temperature influence

Synthesis of orto- and para-aminophenols groups grafted on copolymers is described. The method is applied, extended and optimised for gel-type styrene-divinylbenzene copolymers (S-DVB) with „5” and „7” degree of crosslinking. Keywords: orto- and para-aminophenols groups, styrene-divinylbenzene copolymers

In this paper the numerical simulation of the injection moulding of the total hip prosthesis (acetabular) cup made of UHMWE is carried out in order to determine the optimal conditions for injection process parameter. The numerical simulation was performed using finite element Moldflow Plastic Insight software especially designed for injection molding. Keywords: injection moulding, acetabular cup, hip prosthesis, plastic material, finite element

This paper describes the general concept on structure – liquid crystalline properties relationship for main chain polymers which contain rigid rod – like mesogens. The influence of the mesogenic group, flexible spacers, molecular weight and molecular weight distribution, and of stereospecifical effects on the nature and stability of the mesophases are discussed. Keywords: chain polymers, mesogenic group, stereospecifical effects

Turpentine from pine trees is a renewable source of materials used as feedstock by the chemical industry. The paper presents some ways to use turpentine in the polymer chemistry for preparation of polyterpenes, adhesives, copolymers based on the main components of turpentine, a- and b- pinene respectively, as well as polymeric networks obtained by chemical reactions between turpentine components and a vinyl ester resin. Keywords: turpentine, pinene, polyterpene, copolymerization

The Wittig-Horner reaction is one of the most important reactions in organic chemistry for obtaining alkene. Phase transfer catalyzed reactions are often more easily and cheaply carried out than conventional methods. The copolymer functionalized with diethyl or dibutyl phosphonate were reacted with benzalaldehyde or propionaldehyde to give olefin groups grafted on macromolecular support. The reactions were carried out in benzene or dichloromethane. By using benzaldehyde, higher degree of double bond were obtained. Keywords: polymer-suported Wittig-Horner reagent, phase transfer catalysed, styrene-divinylbenzene copolymers