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The Wittig-Horner reaction is the most general method for regiospecific introduction of carbon-carbon double bounds in organic synthesis. Phase transfer catalyzed reactions are often more easily and cheaply carried out than conventional methods. The paper deals with the synthesis of copolymers functionalized with olefin groups by Wittig-Horner type polymer-analogous reactions in phase transfer catalysis. The copolymer bond aldehyde was reacted with phosphonates to obtain olefin groups grafted on macromolecular support. Keywords: polymer-suported Wittig-Horner reagent, phase transfer catalysed, styrene-divinylbenzene copolymers

In this study, a series of three different thermoplastic poly(ether-urethane-urea)s were synthesized from hexamethylene diisocyanate (HDI), polypropylene glycol (PPG) as macrodiols and hexamethylene diamine (HMDA) as chain extender. The molecular weights of the macrodiols were in the range 400 - 2000 g/mol. The polymers have been characterized by means of 1H-NMR, IR spectroscopy and other techniques. Tensile testing was performed on dumbbell-shaped specimens cut from thin films at room temperature on a TIRAtest 2161 tensile tester (Germany). The hard segment contents were calculated on the basis of urea content, as described by Flory, which represents the best method of the evaluation of the material residing in the hard phases. Keywords: poly(ether-urethane-urea), macrodiols, hard segment contents (HSC)

Segmented poly (ester-urethanes) elastomers based on poly (ethylene diethylene adipate) diols as a soft segment and aromatic diisocyanates in the hard segment were synthesized by a conventional method. The precipitated polyurethane films have been degraded after a limited exposure to reactive agents: 4,4’-methylenebis(phenyl isocyanate) epichlorohydrin and propylene oxide in benzene. The effects on mechanical properties of precipitated polyurethane films were found to be a measure of the degradation due to reactive agents. 4,4’-methylenebis(phenyl isocyanate) and propylene oxide had an increase in the hard segment content which was associated with increased hard domain crystallinity, hardness and improvement in mechanical properties. It is suggested that the superior mechanical performance may be related to interconnecting hard domain texture by cross-linking process. Theis study attempts to correlate the mechanical properties of the precipitated polyurethane films with the nature of the reactive agents. In all cases, the effect of reactive agents was to increase the ultimate tensile strain, except epichlorohydrin. Keywords: poly (ester urethanes) films, reactive agents, mechanical properties

The paper presents two plastic materials from epoxidic resins and compounded polymers families which have properties to visualize stress field produced by mechanical loadings. Using these properties two experimental techniques, photoelasticity and cromoplasticity, were developed for mechanical behaviour investigation of engineering structures. To illustrate the potential of these experimental techniques, in the paper are presented results of a combined analysis undertaken on the state stress in the fastening elements of a hidroagregate, loaded both in elastic and elastoplastic field. Keywords: epoxidic resins, compounded polymers, photoelasticity, cromoplasticity

A series of five new aromatic polyhydrazides containing pendent acetyloxybenzamide groups has been synthesized by low-temperature solution polycondensation of 5-(4-acetyloxybenzamido)-isophthaloyl chloride with dihydrazides of terephthalic, isophthalic, 2,5- or 2,6-pyridin dicarboxylic acids, or with p-aminobenzhydrazide in N-methyl-2-pyrrolidinone (NMP). These polyhydrazides were gradually thermally treated up to 280°C in order to be converted in corresponding poly(1,3,4-oxadiazole)s. The inherent viscosity of polyhydrazides is in the range of 0.31-0.69 dL/g. The polymer structures were confirmed by infrared spectra. The polymers were characterized from solubility and thermal properties point of view. Keywords: polyhydrazides, poly(1,3,4-oxadiazole)s, 5-(4-acetyloxybenzamido) group, thermal stability

Hyperbranched poly (e-caprolactone) copolyesters (hb-PCL) have been prepared by combination of ring opening polymerization (ROP) of e-caprolactone (e-CL) as cyclic AB monomer and concurrent polyconden­sation of 2,2´-bis(hydroxymethyl)butyric acid (BHB) as branching AB2 comonomer unit, using a supported lipase (Candida Antarctica Lipase B, CALB; Novozym 435) as catalyst. By systematic variation of the BHB fraction, hyperbranched copolyester samples with systematically varied degrees of branching (DB) have been obtained. 1H-NMR and 13C-NMR spectra provided detailed information on the DBs. Molecular weights for the hb-PCLs were determined by means of SEC and VPO and exhibited a decreasing tendency with increasing fraction of branching comonomer. Thermal properties of the hb-PCL samples were investigated with respect to the DB. As expected, Tm and DHm were found to decrease with increasing content of BHB (DSC). The crystalline morphology of the samples was investigated by WAXS, revealing the DB-dependent existence of two crystalline polymorphs with different density and chain packing. Light microscopy studies demonstrated both a different crystal habitus for the hyperbranched copolymers, as well as a decrease of the crystalline fraction for the hb-PCL samples in comparison to the linear analogue. With increasing DB, the crystallites became small and irregularly shaped, indicating phase segregation in crystallizable and non-crystallizable material during crystallization. Solution viscosimetry showed low specific and intrinsic viscosity for the branched materials and demonstrated that the hyperbranched samples assume an increasingly compact solution structure with increasing extent of branching. For both CHCl3 and THF solutions, an increase of the temperature from 20 to 50oC results in a decrease of [h] for all analyzed hb-PCLs. Keywords: copolyesters, hyperbranched polymers, degree of branching, polymer morphology

Various bismaleimides and biscitraconimides containing ester and ether units in the main chain and having SO2 groups were synthesized. Monomers with ester units were synthesized by condensation between 3(4)-maleimidobenzoyl chloride or 4-citraconimidobenzoyl chloride with 4,4-hydroxyphenyl sulfone. Bismaleimide and biscitraconimide with ether units were prepared by reaction between maleic anhydride or citraconic anhydride with 4,4-bis (4-aminophenoxy)diphenyl sulfone. Keywords: bismaleimide & biscitraconimide monomers

A recyclable material, that can be incinerated under safety conditions, for humans and environment, the polyvinyl chloride (PVC) is still a largely used polymer, as a compound, inclusively. The PVC -TPU compounds are of interest due to their attrition resistance, chemical resistance, resistance to migration in solvents and oils (low extractibility), high bending under negative temperatures, low densities and erosion, stability to high temperatures, easy processing into finite article, cost efficient. All these properties are superior to a flexible PVC (hot masticated). The paper presents a study on dependency of some usage properties of PVC - TPU compounds on compounds composition. The results of the modification study of PVC with TPU are that new compounds have: the density within the range 1.18 – 1.3 g/cm3 , erosion within the domain 107 – 142 mm3, number of bendings up to breaking at positive temperatures, over 500 000, number of bendings up to cracking at –8 0C, over 500 000 bendings. Keywords: polyvinil chloride, thermoplastic polyurethane, physical modification, abrasion, density

The atactic polypropylene (APP) recovery as hydro insulation membranes and / or bitumen presents two main advantages: the great quantities that can be reprocessed and the elevated usage life of the obtained products, a consequence of lack of the photo and thermal degradation during usage. It is well know that the photo and thermal degradation rapidly diminishes the utilization properties, namely the usage life. The recovery into hydro insulation membranes and / or bitumen is possible if the APP was selected based on thermo – oxidative stability criteria typically for a good incorporation into the melt bitumen at 180 0 C for 4 – 10 hours and for RTFOT or TFOT tests. The RTFOT thermo – oxidative stability criterion, according to which the mass loosing at 163 0C for 80 min. must be smaller than 0, 8 %, is fulfilled only if the APP has a weight molecular mass greater than 8000 and a solid consistency. If these two criteria are not fulfilled the APP can be recovered as hot melt adhesives. Keywords: atactic polypropylene, practical application, hydro insulation membranes and bitumen

For the transport of gas or water, it is generally welding by heater which is used for the butting together of the tubes. The quality of the joint is influenced by the choice of the parameters of welding, the geometry of the tubes and the environment. It is not possible of determine analytically the optimal parameters of welding according to dimensions of the tubes. This paper describes the models of extrapolation, which makes it possible to transpose the optimal parameters and strong thickness of welding for tubes of large diameter previously determined using smaller tubes. The first chapter of the paper is primarily centred on an analysis of the process of welding end to end by heater. A mathematic description of the various phases of the process leads to coefficients without dimension. The models used for the determination of the parameters of welding result in the invariance of these coefficients. Keywords: optimization, mathematical model, heated tool butt welding, hydro – carbon (HD-PE), transporting pipelines