Wyniki wyszukiwania - BazTech

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Fireproof, solid state epoxy resins

Brzozowski Z. K., Staszczak S., Hadam Ł., Zatorski W., Rupiński S., Bogdał D.

Polimery

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2007

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T. 52, nr 1

29-33

EN

Solid state epoxy resins were synthesized in the reactions of the systems: 1,1-dichloro- -2,2-bis(4-hydroxyphenyl)ethylene (BPC II) and 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), mixed in various weight ratios, with one of two low-molecular weight epoxy resins, Epidian 5Ž or diglycidylether of 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene (DGEBC II). Additionally the series of the samples synthesized with use of DGEBC II but with addition of red phosphorus as flame retardant were prepared. It was found, on the basis of limiting oxygen index (LOI) measurements, that the flammability of the samples decrease (higher values of LOI) with increase in BPC II weight part in the mixture with bisphenol A, for all the series of samples prepared. Solid state resins synthesized with the use of DGEBC II were less flammable than similar samples with bisphenol A. Addition of red phosphorus increased significantly LOI values, however, caused deterioration of optical properties of the resins investigated. The samples characterized with low flammability were selected for the syntheses with addition of zinc stannate (ZS) or zinc hydroxystannate (ZHS) as flame retardants. The values of LOI of the products obtained were determined (Table 2). It was found that the addition of 2-3 wt. % of ZS or ZHS significantly improves LOI values not causing the deterioration of optical properties.

PL

W reakcjach układu 1,1-dichloro-2,2-bis(4-hydroksyfenylo)etylenu (BPC II) i 2,2-bis(4- -hydroksyfenylo)propanu (bisfenol A) zmieszanych w różnych stosunkach masowych i jednej z dwu małocząsteczkowych żywic epoksydowych: "Epidian 5Ž" lub eter diglicydowy 1,1-dichloro-2,2-bis(4- -hydroksyfenylo)etylenu (DGEBC II) zsyntetyzowano stałe żywice epoksydowe [równanie (1), tabela 1]. Dodatkowo przygotowano serię próbek zsyntetyzowanych z użyciem DGEBC II ale z dodatkiem fosforu czerwonego jako antypirenu. Na podstawie pomiarów indeksu tlenowego (LOI) stwierdzono, że palność próbek spada (wyższe wartości LOI) wraz ze wzrostem udziału masowego BPC II w mieszaninie z bisfenolem A w każdej otrzymanej serii próbek (rys. 1). Stałe żywice zsyntetyzowane z udziałem DGEBC II były mniej palne niż analogiczne próbki z udziałem bisfenolu A. Dodatek fosforu czerwonego znacznie zwiększał wartości LOI natomiast powodował pogorszenie właściwości optycznych badanych żywic. Wybrane próbki charakteryzujące się małą palnością wybrano za podstawę do syntez z użyciem cynianu cynku (ZS) lub hydroksycynianu cynku (ZHS) jako antypirenów i wyznaczono wartości LOI otrzymanych produktów (tabela 2). Ustalono, że dodatek 2-3 % mas. ZS lub ZHS zdecydowanie podwyższa wartości LOI nie powodując pogorszenia właściwości optycznych.

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Rozpuszczalne w wodzie karbamoiloetylowane pochodne skrobi ziemniaczanej. Cz. I. Synteza i struktura

Rupiński S., Brzozowski Z. K., Skwara K.

Polimery

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2005

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T. 50, nr 11-12

821--830

PL

Opisano dwie metody syntezy karbamoiloetylowanych pochodnych skrobi (CrES) obejmujące etapy degradacji (chemicznej bądź enzymatycznej pod wpływem a-amylazy) oraz etap reakcji addycji z akryloamidem. Zbadano wpływ warunków degradacji enzymatycznej (biodegradacji) na rozpuszczalność w wodzie CrES, lepkość jej roztworów wodnych, stopień podstawienia (DS) i ciężar cząsteczkowy. Scharakteryzowano wpływ opisanej modyfikacji skrobi na zmiany struktury jej powierzchni.

EN

Water-soluble starch derivatives (CrES) containing carbamoylethyl groups were synthesized using two methods. The first based on chemical degradation of native potato starch under the influence of KOH or NaOH and subsequent reaction of addition with acryloamide. The other based on carbamoylethylation of native starch in such reaction and subsequent enzymatic biodegradation of CrES obtained using a-amylase. The effects of biodegradation conditions, namely: catalyst type and concentration [Ca(OH)2, KOH], time and temperature of the process and a-amylase concentration on CrES solubility in the water and viscosity of aqueous solutions obtained (Table 1 and 6) as well as on the degree of substitution (DS, Table 2-5). The lowering of molecular weight of starch products after degradation, either chemical or enzymatic one, positively influences the solubility of CrES in water (results of MALDI-TOF measurements, Fig. 1, 2 and 6). The modification causes also the changes in the surface structure of CrES facilitating its dissolution in water (results of SEM microscopic investigations, Fig. 3 and 7). Chemical structure of CrES was confirmed by FT-IR method (Fig. 4, 5 and 8).

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Modyfikaty skrobii o dużej lepkości

Rupiński S., Brzozowski Z. K., Skwara K., Zatorski W.

Przemysł Chemiczny

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2003

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T. 82, nr 8-9

1157-1160

PL

Przedstawiono wyniki badań nowo opracowanych pochodnych skrobi o dużej lepkości, zawierających grupy karbamoiloetylowe. Badano reakcje fosforanu diskrobiowego z akryloamidem na drodze addycji. Wielkościami poddanymi badaniom były: zawartość wodorotlenku sodu, czas i temperatura reakcji. Scharakteryzowano podstawowe właściwości tych polimerów przy użyciu różnych technik instrumentalnych, takich jak analiza elementarna, FT-IR oraz badania lepkości. Stwierdzono, że otrzymane pochodne skrobi są dobrze rozpuszczalne w wodzie i tworzą 4–8-proc. żele.

EN

Di-starch phosphate, 5 g in 50 mL H2O at 30°C, alkalized with 0.75 g NaOH (in 20 mL H2O), was carbamoylethylated 6 h with 2.5 g acrylamide (in 20 mL H2O) at 45°C, degree of substitution, 0.207% (max). The mixture was neutralized at 25°C to pH 7 with aq. 10% HCl; the product was precipitated with 1000 mL MeOH and dried at 75–80°C. At NaOH > 0.80 g, the degree of substitution fell owing to hydrolysis of amide groups to -COOH, and NH3 was released. At shear rates of 5–10 s-1, the (25°C, aq. 5%) viscosities of the products modified 2.5 h and 6 h were resp. 24 and 16 Pa·s vs. the 8 Pa·s of the starting di-starch phosphate. Product structure was confirmed by elementary analysis and FTIR.

4

Synthesis of PUR and PUR-PIR foams with bromine flame retardant

Zatorski W., Brzozowski Z. K., Łebek K., Rupiński S.

Polish Journal of Chemical Technology

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2003

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Vol. 5, nr 4

17-19

EN

2,3-DIBROMO-2-BUTENE-l,4-DIOL (DBBD) was found to be one of most effective bromine flame retardants used to synthesis fire-safe rigid polyurethane foams (PUR). The compositions of DBBD with structural changes of polyurethane foams were investigated. The propriety of two kinds of foams: polyurethane (PUR) and polyurethane-isocyanurate (PUR-PIR) frothed with DBBD were received and compared during experiments. Received foams were characterized by improved fire-resistant properties without worsening useful proprieties. Effect of synergism in extinguishing was obtained through the use of stop- burning chemical structure: aliphatic bromine and isocyanurate rings. The ozone friendly blowing agent was applied.

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Synthesis and properties of carbamoylethyl starch

Rupiński S., Brzozowski Z. K.

Polimery

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2003

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T. 48, nr 2

122-129

EN

A new ecological and simple method of acrylamide derivatives of starch (carbamoylethyl starch CrES) obtaining, consisting in starch modification using Michael addition reaction in base environment, was elaborated. The course of starch degradation (with the aim to decrease its molecular weight) was investigated as well as the course of substitution reaction of starch with acrylamide dependently on the amounts (concentrations) of bases used (NaOH and KOH). The effects of temperature, reaction time and amount (part) of acrylamide added on degree of substitution (DS) were studied. CrES structure was confirmed using the following methods: MALDI TOF, FT-IR spectroscopy, DSC and X-ray diffractometry. Molecular weight distribution of starch modification, what can be controlled by degradation time, was determined using massspectrometry. Modified starch was well soluble in water and their aqueous solutions, concentrated up to 40%, were obtained. The effects of solution concentration and degree of substitution on the solution viscosity dependently on the shear rate have been studied. The influence of DS value and temperature on the solubility of CrES in water has been established too.