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Synthesis and properties evaluation of quaternized polyurethanes as antibacterial adhesives

P. Hu, A. Greiner, S. Agarwal

J. Polym. Sci. Part A: Polym. Chem., 2019, doi:10.1002/pola.29321


We present new side‐chain quaternized polyurethanes as antibacterial adhesives made by polyaddition polymerization followed by quaternization for different time intervals. The degree of quaternization of N‐diol units in the polymer is changed from 13.6 to 99.0 mol % (almost complete) for tuning the antibacterial action (leaching/contact type) and studying effect on adhesive strength. The degree of quaternization of about 26 mol % provided the nonleaching antibacterial effect with adhesive strength more than 60 N cm−2 on aluminum and glass substrates. The increase in the degree of quaternization enhanced polymer polarity shifting nonleaching (contact type) antibacterial behavior to the leaching type but maintaining the high adhesive strengths.


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New Review  by S. Agarwal, S. Jiang, Y. Chen published in Macromol. Mater.

S. Agarwal, S. Jiang, Y. Chen

Macromol. Mater. Eng., 2018, 1800548


Welcome to Macromolecular Chemistry II

Spruch der Woche

Perfektion ist erreicht, nicht, wenn sich nichts mehr hinzufügen lässt, sondern, wenn man nichts mehr wegnehmen kann. (Antoine de Saint-Exupery) (Perfection is achieved, not when nothing more can be added, but when nothing more can be taken away (Antoine de Saint-Exupery))

"Die reinste Form des Wahnsinns ist es, alles beim Alten zu lassen und gleichzeitig zu hoffen, dass sich etwas ändert. (The sheerest madness is to leave everything the way it is and to simultaneously hope that something will change)" Albert Einstein

"The fate of genius is to be misunderstood, but not everything is a misunderstood genius" Ralp Waldo Emmerson (1803-1882)

"Facts do not cease to exist because they are ignored” (Aldous Huxley, author of Brave New World)

"Die Ablehnung Unwichtiges zu tun, ist eine entscheidende Voraussetzung für den Erfolg“ Sir Alexander MacKenzie

"An idea that is not dangerous is unworthy of being called an idea at all“ von Oscar Wilde (Eine Idee, die nicht gewagt ist, verdient es nicht, überhaupt eine Idee genannt zu werden)


News 16.01.2019

Controlled-Release LCST‐Type Nonwoven Depots via Squeezing-Out Thermal Response

F. Käfer, R. Vilensky, G. Vasilyev, E. Zussman, S. Agarwal

Macromol. Mater. Eng. 2018, 1800606.


A novel thermoresponsive fibrous matrix as controlled release depots upon heating is described. The matrix is composed of electrospun fibers of a lower critical solution temperature (LCST)‐type poly(methacrylamide‐co‐N‐tert‐butylacrylamide‐co‐4‐acryloylbenzophenone) P(MAAm‐NtbAAm‐ABP) copolymer. Spherical particles, simulating depots of drugs, are embedded with liquid‐filled inter‐fiber spaces (pores). On heating above 25 °C up to 45 °C, the nanofibers undergo a contraction of about 40%. This solid deformation is attributed to the LCST transition. Fibrous matrix contraction drives expulsion of depots and water solution stored in the pores of the matrix, as evidenced by in situ observations. The liquid flow in the deformable porous medium demonstrates liquid drainage from the matrix as a function of temperature. Experimental results reveal that 70% of the particles are expelled from the matrix upon heating to 45 °C from room temperature. The presented particles encapsulation and release model system using LCST‐type fibrous matrix can be used as a transdermal patch.

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