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1

Hydrophilic films based on starch and carboxymethyl starch

100%

Wilpiszewska K.

Polish Journal of Chemical Technology

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2019

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tom Vol. 21, nr 2

26--30

EN

The hydrophilic films based on starch and carboxymethyl starch (CMS) were obtained using cast method. The effect of CMS content on the physicochemical properties of prepared films were evaluated. With increasing content of starch derivative the moisture absorption, solubility in water as well as swelling ratio increased. The highest values of mechanical parameters (tensile strength and Young’s modulus) were determined for the starch/CMS film containing the lowest CMS amount, i.e. 10 wt.% (1.1 MPa, 15 MPa, respectively). For the same system the lowest moisture absorption, solubility in water as well as swelling ratio were reported. Thus, it could be concluded that for this system the highest crosslinking density has been achieved, what was confirmed by DMTA results. Such a film could potentially find application in food or agricultural industry.

2

The effect of cross-linking agent amount and type on the sorption properties of starch graft polyacrylamide and poly(acrylic acid) copolymers

63%

Schmidt B. , Wilpiszewska K.

Polish Journal of Chemical Technology

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2024

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tom Vol. 26, nr 4

81--86

EN

In free radical polymerization initiated by 2,2’-azobis(2-methylpropionamidine) dihydrochloride, grafted starch copolymers with a weight ratio of acrylamide to acrylic acid of 1:2 were obtained. Three acrylic products were used to cross-linking starch copolymers: MBA, PETIA and EBECRYL 40 in amounts of: 0.2, 0.4, 0.6 and 1.0 wt.%. Materials were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry and reoviscometry. The sorption properties of starch copolymers were confirmed by sorption tests: water absorption, swelling in water and sorption of cations: trivalent iron and divalent copper. The highest water absorption is characteristic of materials cross-linked with MBA (1800%), then PETIA (1400%) and EBECRYL 40 (850%). On the other hand, the best swelling results are in the sequence PETIA > MBA > EBECRYL (1050% > 900% > 570%). The most effective sorbent of cations is the copolymer cross-linked with MBA. Solution purifications of 90% and 45% were obtained for Fe+3 and Cu+2, respectively.

3

Starch plasticization with choline dihydrogencitrate-based deep eutectic system

63%

Wilpiszewska K. , Skowrońska D.

Polish Journal of Chemical Technology

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2022

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tom Vol. 24, nr 3

53--59

EN

Two-component deep eutectic solvents (DES) based on choline dihydrogencitrate and glycerol or urea were tested as starch plasticizers. Thermal analysis techniques were applied to characterize the properties of starch/DES systems. The X-ray diffractometry measurements revealed a significant decrease in crystallinity indicating that used DES exhibited the ability to penetrate the ordered regions of potato starch, which is a necessary feature of a true plasticizer. However, the differential scanning calorimetry and dynamic thermal analysis results surprisingly showed an increase of Tg of starch materials indicating chemical crosslinking at elevated temperature. The eutectic solvents based on choline dihydrogencitrate could act as a plasticizer and a simultaneously crosslinking agent.

4

Potato starch plasticization by natural deep eutectic solvent

63%

Skowrońska D. , Wilpiszewska K.

Polimery

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2023

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tom Vol. 68, nr 9

480--486

EN

A natural deep eutectic solvent (NADES) based on choline chloride and malic acid was used to plasticize potato starch. The influence of starch gelatinization temperature, NADES content and the method of its incorporation (before and after gelatinization) on starch plasticization was investigated. Polymer-plasticizer interactions were studied using MDSC, DMTA, XRD and FTIR-ATR methods. The viscosity of starch solutions as well as the mechanical properties and water absorption of the obtained films were determined. Gelatinization conditions had a significant impact on the viscosity of starch solutions and the physicochemical properties of the obtained films. The cross-linking reaction between starch and malic acid was confirmed by MDSC, DMTA, and mechanical tests. Slight recrystallization of starch was observed after 12 months of storage.

PL

W pracy do plastyfikacji skrobi ziemniaczanej użyto naturalnej cieczy głęboko eutektycznej (NADES) na bazie chlorku choliny i kwasu jabłkowego. Zbadano wpływ temperatury żelowania skrobi, zawartości NADES oraz sposobu jego wprowadzenia (przed i po żelowaniu) na plastyfikację skrobi. Oddziaływania polimer-plastyfikator badano przy użyciu metod MDSC, DMTA, XRD i FTIR-ATR. Oznaczono także lepkość roztworów skrobi oraz właściwości mechaniczne i nasiąkliwość otrzymanych folii. Warunki żelowania miały istotny wpływ na lepkość roztworów skrobi oraz właściwości fizykochemiczne otrzymanych folii. Reakcję sieciowania skrobi z kwasem jabłkowym potwierdzono za pomocą MDSC, DMTA i badań mechanicznych. Po 12 miesiącach przechowywania zaobserwowano nieznaczną rekrystalizację skrobi.

5

Influence of the ester block polymerization degree on the structure and properties of ester-ether-amide block terpolymers

51%

Rokicka J. , Janik J. , Schmidt B. , Wilpiszewska K.

Polimery

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2024

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tom Vol. 69, nr 2

75--85

EN

New multi-block thermoplastic elastomers (TPEEA) were obtained, consisting of a crystalline amide block (domains), an amorphous ether block (continuous phase) and an ester block with a variable degree of polymerization, which acts as a compatibilizer. The presence of large interfacial areas was observed. It was found that ester blocks with a molecular weight <600 g/mol mix with other blocks, modifying the phases that constitute them and stabilizing the micro- and nanophase structure of the entire system. Short ester blocks act as nucleation precursors, and in the hard phase they have plasticizing properties.

PL

Otrzymano nowe wieloblokowe elastomery termoplastyczne (TPEEA), składające się z krystalicznego bloku amidowego (domeny), amorficznego bloku eterowego (faza ciągła) oraz bloku estrowego o zmiennym stopniu polimeryzacji, który pełni funkcję kompatybilizatora. Zaobserwowano obecność dużych obszarów międzyfazowych. Stwierdzono, że bloki estrowe o masie cząsteczkowej <600 g/mol mieszają się z innymi blokami, modyfikując tworzące je fazy i stabilizując strukturę mikro- i nanofazową całego układu. Krótkie bloki estrowe pełnią funkcję prekursorów zarodkowania, a w fazie twardej mają właściwości uplastyczniające.

6

Wytwarzanie i badanie mieszanin poli(tereftalanu etylenu) i poliwęglanu (PET/PC) z odpadowych butelek PET i płyt CD

51%

Janik J. , Schmidt B. , Wilpiszewska K. , Rokicka J.

Przemysł Chemiczny

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2022

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tom T. 101, nr 2

140--146

PL

Przedstawiono badania nad mieszaninami poli(tereftalanu etylenu) pochodzącego z rozdrobnionych butelek typu PET oraz poliwęglanu z rozdrobnionych płyt CD w aspekcie zagospodarowania tych odpadów metodą recyklingu materiałowego, a także wytworzenia nowego materiału w postaci mieszanin PET/PC. Wytworzono za pomocą wytłaczarki dwuślimakowej granulaty mieszanin zawierające 5–95% mas. PC. Granulat PET/PC, jak również wyjściowe polimery PET i PC, poddano procesowi wtryskiwania w celu uzyskania kształtek do badań. Ocenę prowadzono pod kątem właściwości mechanicznych (wytrzymałość na rozciąganie i zginanie, udarność, twardość), termicznych (temperatura zeszklenia, krystalizacji, topnienia, mięknienie wg Vicata), reologicznych (lepkość stopu w temperaturze przetwórstwa), fizycznych (gęstość, chłonność wody) oraz morfologii w celu określenia wpływu udziału poszczególnych polimerów w mieszaninie PET/PC na badane parametry.

EN

Waste poly(ethylene terephthalate) (PET) and polycarbonate (PC) were granulated with a twin-screw extruder to obtain blends contg. 5-95% of each component. The PET/ PC granulates as well as the starting PET and PC polymers were subjected to the injection process to obtain test specimens. Phys. (d., water absorption), thermal (glass transition temp., crystallization temp., melting point and Vicat softening point), mech. (tensile and bending strength, impact strength, hardness), rheological properties (melt viscosity at processing temp.) and morphology were tested. PET/ PC mixts. with strictly defined parameters showed the good functional properties, comparable or better than the initial polymers.

7

Epoksydowane oleje roślinne : zastosowanie w nowoczesnych materiałach polimerowych

45%

Janus E. , Musik M. , Wilpiszewska K. , Sałaciński Ł. , Milchert E.

Wiadomości Chemiczne

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2021

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tom [Z] 75, 9-10

1395--1411

EN

The growing, global concern for the natural environment contributes to the intensive research on at least partial replacing of petroleum-based raw materials with bio-renewable resources on an industrial scale. The chemical composition and oligomeric nature of plant oils make them a promising bio-renewable base for development of new polymer materials. The conversion of plant oils and fats to epoxidized plant oils (EO) and polyols are the processes intensively studied. Epoxides based on soybean oil, i.e. one of the most easily available vegetable oils, have a high potential for polymeric materials preparation. In addition, linseed and castor oils are of great importance in this area as well. This article presents the latest achievements in the production of novel polymer materials based on epoxidized vegetable oils and their derivatives. The importance and application of EO for polymer materials should be considered multidirectional. Epoxidized plant oils are the platform chemicals for polyethers, polyesters, polyurethanes and polyhydroxyurethanes, but also can act as modifiers for natural and synthetic polymers. Polymers based on epoxidized vegetable oils in combination with filler – including more and more popular natural fibers, allow to obtain biocomposites. Applying bioresin and natural reinforcement reduces the carbon footprint. Moreover, such materials may exhibit competitive properties against petrochemical polymer products and meet the requirements of the automotive, packaging, furniture, and construction industries. Additionally, obtaining materials showing functional properties, including shape memory and self-healing ability is also possible.