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1
Content available Fotopolimeryzacja (met)akrylanów w masie
Gziut Konrad, Kowalczyk Agnieszka
Wiadomości Chemiczne
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2019
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[Z] 73, 7-8
443--459
EN
Meth(acrylate) polymers are prepared by polymerization according to the radical mechanism. This is possible due to the occurrence of unsaturated double bonds (vinyl groups) in monomers. Meth(acrylate) polymerization reaction is usually carried out in organic solvents using thermal initiators which decompose at elevated temperature to give radicals. An appropriately selected initiator or electromagnetic radiation (e.g. UV light) can be used to initiate the polymerization process. In this case the process is called photopolymerization. Due to the fact that the radical photopolymerization mechanism of met(acrylates) has already been well understood, and the advantages of lightinduced polymerization offer enormous possibilities, this technology still attracts the attention of researchers and industrialists, which results in its continuous development. Meth(acrylates), which are very reactive, are suitable compounds for this technology. Light induced process of transformation these molecules into polymer can be carried out in a very short time. In addition, a wide range of monomers allows to obtain products with various properties. Typically, photopolymerization is associated with the cross-linking of polymers that form part of photocurable compositions, as a result of which, for example, varnish coatings, dental fillings or self-adhesive materials are produced. In this article, contemporary literature on the photopolymerization of (meth)acrylates with reference to the photopolymerization in bulk method is also pointed out. This technique allows to obtain polymer syrups - a polymer solution in unreacted monomers. These viscous liquids are very interesting semi-finished products (free of solvent and almost ready for application) for the preparation of various polymer materials, especially coatings and adhesives.
2
Content available remote Nanocomposites obtained by photopolymerization of (methacrylate monomer)/(methacrylate functionalized polyhedral oligomeric silsesquioxane) system
Andrzejewska E., Marcinkowska A., Wegner K.
Polimery
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2011
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T. 56, nr 1
63-66
EN
Nanocomposites based on a mixture of poly(ethylene glycol) dimethacrylate (PEGDM) with poly(ethylene glycol) monomethacrylate (PEGMM) (mass ratio 1:1) and propyl methacrylate functionalized polyhedral oligomeric silsesquioxane (M-POSS) were obtained by photopolymerization. Both the polymerization kinetics of compositions (with M-POSS contents loadings between 0 and 100 wt. %) and mechanical properties (with M-POSS contents between 0 and 35 wt. %) were investigated. It was found that M-POSS addition accelerates or retards the polymerization, depending on its concentration and reduces double bond conversion, however significantly increases modulus (E), tensile stress (σM) and hardness (H) of the resulting nanocomposite.
PL
Otrzymano nanokompozyty na bazie równowagowej mieszaniny mono- i dimetakrylanu glikolu poli(oksy)etylenowego oraz poliedrycznego silseskwioksanu funkcjonalizowanego grupami metakryloksypropylowymi (M-POSS). Zbadano kinetykę fotopolimeryzacji kompozycji zawierających 0-100 % mas. M-POSS oraz właściwości mechaniczne [wytrzymałość na rozciąganie (σM), moduł (E), wydłużenie przy zerwaniu (εB), twardość wg Shore'a A (H)] produktów zawierających 0-35 % mas. M-POSS (rys. 3). Stwierdzono, że dodatek M-POSS zwiększa szybkość fotopolimeryzacji (Rp) próbek o średnich stężeniach M-POSS (do 15 % mas.), a zmniejsza w przypadku próbek o stężeniach wyższych (rys. 2). Stopień konwersji wiązań podwójnych (pf) maleje ze wzrostem zawartości M-POSS (rys. 2b). Pomimo tego, zaobserwowano wzrost sztywności materiału przejawiający się gwałtownym wzrostem wartości modułu E (w próbce o zawartości POSS wynoszącej 35 % mas. aż 30-krotnym), wzrostem σM (nawet 4-krotnym), spadkiem εB oraz znaczącym wzrostem H (ok. 3-krotnym w próbce o zawartości M-POSS 35 % mas.).
3
Content available Formation and properties of hydrogel membranes based on cross-linked copolymers of methacrylates and water-soluble polymers
Suberlyak O., Melnyk J., Skorokhoda V.
Engineering of Biomaterials
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2009
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Vol. 12, no. 86
5-8
EN
Experimental results concerning the effect of composition, nature of polymeric matrix, monomer and solvent on the structure, physico-mechanical and selective-transport characteristics of hydrogel membranes based on cross-linked grafted copolymers of methacrylates and water-soluble polymers (polyvinyl-pyrrolidone, polyvinyl alcohol) have been presented. Methods of high-penetrating hydrogel membranes formation have been developed and capability of directional control of their structure and operational characteristics has been determined.
4
Content available remote Otrzymywanie i właściwości usieciowanych metakrylanów, pochodnych bezwodnika maleinowego
Podgórski M., Matynia T.
Przemysł Chemiczny
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2008
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T. 87, nr 8
874-880
5
Content available remote Synthesis and characteristics of salen catalysts supported on hydroxyl functionalized methacrylic copolymers
Bukowski W., Bukowska A.
Polish Journal of Chemical Technology
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2006
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Vol. 8, nr 3
76-78
EN
Salen supported polymer catalysts were obtained as a result of a multi-stage chemical modification of three-components 2-hydroxyethyl and 2-hydroxypropyl metacrylate copolymers. The catalysts were tested in the model reaction of acetic acid with epichlorohydrin.
6
Content available remote Preparation of polymer blends by means of photopolymerization of monomer/polymer systems
Janaszczyk M., Andrzejewska E., Andrzejewski M.
Polish Journal of Chemical Technology
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2006
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Vol. 8, nr 3
84-86
EN
Two types of polymer blends: poly(glycidyl methacrylate)/poly(propylene glycol) (PPG) and poly(triethylene glycol dimethacrylate)/PPG were obtained by means of photopolymerization of PPGs solutions in corresponding monomers. During the polymerization phase separation occurred. The range of conversions where cloud points occur were determined as a function of the molecular weight (MW) of PPG used. It was found that the polymerization rate was controlled by the initial viscosity of the system and the quality of PPG used as the solvent.
7
Content available remote Synteza i kopolimeryzacja monomerów metakrylowych zawierających pierścienie kumarynowe i ftalimidowe
Stępień I., Bogdał D.
Czasopismo Techniczne. Chemia
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2004
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R. 101, z. 1-Ch
141-146
PL
Opracowano metody syntezy monomerów metakrylanu N-(2-ftalimidolilo) etylu (FEM) oraz 7-dietyloamino-3-(2-metakryloiloetoksy)karbonylokumary (MK), na drodze kondensacji Knoevenagela i metody aktywowanych estrów. Wszystkie reakcje przeprowadzono tak, aby charakteryzowały się prostotą ich przeprowadzania oraz małą ilością etapów pośrednich. Następnie monomery kopolimeryzowano tak, aby otrzymać polimer (FEM% MK) o molowej zawartości monomeru kumarynowego 0,5, 1, 2, 8%.
EN
Methods of synthesis, such as Knoevenagela condensation and active esters metod, of N-(2-phtalimidazolyl)ethyl methacrylate (FEM) and 7-diethyl-aminocoumarin-3-carbo-xylic acid 2-(methacryloyloxy)ethyl ester (MK) were developed. All reactions were carried out in a manner to reduce reaction times and decrease number of intermediate stages. Monomers were copolymerized to give (99.5:0.5), (99:1), (98:2), and (92:8 mol/mol) FEM%MK copolymers.
8
Content available remote Żyjąca polimeryzacja jonowa
Stolarczyk J.
Polimery
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2002
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T. 47, nr 10
679-684
PL
Przedstawiono (w nawiązaniu do Kongresu IUPAC Macro 2000) przegląd prac nad żyjącą polimeryzacją jonową, opublikowanych w głównej mierze w ostatnich latach. Są to przede wszystkim artykuły dotyczące anionowej polimeryzacji meta-krylanów i akrylanów, jednak procesy żyjące badano również w odniesieniu do polimeryzacji szeregu innych monomerów zarówno winylowych, jak i heterocyklicznych (z otwarciem pierścienia). Opisano nowe i modyfikowane układy inicjujące stosowane w żyjącej polimeryzacji. W przeglądzie uwzględniono również syntezy różnych makromonomerów oraz tele-chelicznych homo- i kopolimerów o różnorodnej (np. gwiaździstej) architekturze.
EN
A review of research works on ionic living polymerization, published mainly in recent years, has been presented. In majority the publications concern anionic polymerization of methacrylates and acrylates, however living polymerization has been investigated also for vinyl monomers as well as for heterocyclic ones (ring opening polymerization). New and modified initiating systems used in the living polymerization have been described. The syntheses of various macromonomers as well as telechelic homopolymers and copolymers with various architecture (e.g. star-shaped one) have been also included in the review.
9
Content available Permeability of Medical Gloves to Mono- and Dimethacrylate Monomers in Dental Restorative Materials
Lonnroth E. C., Ruyter I. E.
International Journal of Occupational Safety and Ergonomics
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2002
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Vol. 8, No. 4
497--509
EN
Dental personnel manually handle methacrylate-based restorative materials, which can cause skin irritation and allergies. The protection given by different types of medical gloves is not well known. Breakthrough time (BTT, min) was used as a measure of protection according to a European standard, using 2 test mixtures consisting of respectively 3 and 5 monomers. Fourteen gloves representing natural rubber latex, synthetic rubber, and synthetic polymeric material were tested. The BTT ranged from some minutes to more than 2 hrs for the 4 monomers with a molecular mass less than 300. The longest protection was recorded for Nitra Touch (nitrile rubber), Tactylon (synthetic rubber), and Metin (PVC).
10
Content available remote Analiza przebiegu reakcji metakrylanu 2-hydroksyetylu z izocyjanianem fenylu
Lubczak R.
Zeszyty Naukowe Politechniki Rzeszowskiej. Chemia
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2001
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z. 17 [184]
77-89
PL
W pracy stwierdzono, że w reakcji metakrylanu 2-hydroksyetylu z izocyjanianem fenylu nie tworzy się oczekiwany uretanoester (N-fenylokarbaminian 2-metakryloiloksyetylu), ale mieszenina produktów jego przemiany, to jest bis(fenylo-karbaminianu) etylenu i dimetakrylanu etylu. Taki przebieg reakcji wykazano, stosując instrumentalne (IR i ¹H-NMR) oraz chromatograficzne metody badań uzyskanych produktów.
EN
In the reaction of 2-hydroxyethyl methacrylate with phenyl isocyanate, the expected urethane ester (2-methacryloiloxyethyl N-phenylcarbamate) has been found not to be formed, but a mixture of products of transforraation of the latter, namely ethylene bis(phenylcarbamate) and ethylene dimethacrylate. The reaction products were identified by using spectral (IR and ¹H-NMR) and chromatographic methods.
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