Interaction of synthetic polymers with components of the living materials

1979 ◽  
Vol 2 (S19791) ◽  
pp. 215-231 ◽  
Author(s):  
Jaroslav Kálal
2022 ◽  
Author(s):  
Hyuna Jo ◽  
Seunghyun Sim

With advances in the field of synthetic biology increasingly allowing us to engineer living cells to perform intricate tasks, incorporating these engineered cells into the design of synthetic polymeric materials will enable programming materials with a wide range of biological functionalities. However, employable strategies for the design of synthetic polymers that form a well-defined interface with living cells and seamlessly integrate their functionalities in materials are still largely limited. Herein, we report the first example of living materials constructed with a dynamic covalent interface between synthetic polymers and living B. subtilis cells. We showedthat 3-acetamidophenylboronic acid (APBA) and polymers of APBA (pAPBA) form dynamic covalent bonds with available diols on the B. subtilis cell surface. Importantly, pAPBA binding to B. subtilis shows a multivalent effect with complete reversibility upon addition of competitive diol species, such as fructose and sorbitol. On the basis of these findings, we constructed telechelic block copolymers with pAPBA chain ends that crosslink B. subtilis cells and produced self- standing living materials. We further demonstrated that the encapsulated cells could be retrieved upon immersing these materials in solutions containing competitive diols and further subjected to biological analyses. This work establishes the groundwork for building a myriad of synthetic polymeric materials integrating engineered living cells and provides a platform for understanding the biology of cells confined within materials.


Author(s):  
P. Sadhukhan ◽  
J. B. Zimmerman

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.


2013 ◽  
Vol 10 (2) ◽  
pp. 51
Author(s):  
Siti Farhana Zakaria ◽  
Keith R Millington

Polymers and organic materials that are exposed to sunlight undergo photooxidation, which leads to deterioration of their physical properties. To allow adequate performance under outdoor conditions, synthetic polymers require additives such as antioxidants and UV absorbers. A major problem with optimising polymer formulations to maximise their working life span is that accelerated weathering tests are empirical. The conditions differ significantly from real weathering situations, and samples require lengthy irradiation period. Degradation may not be apparent in the early stages of exposure, although this is when products such as hydroperoxides are formed which later cause acceleration of oxidation. A simple way of quantifying the number of free radicals presents in organic materials following exposure to light or heat is by measuring chemiluminescence (CL) emission. Most polymers emit CL when they undergo oxidative degradation, and it originates from the bimolecular reaction of macroperoxy radicals which creates an excited carbonyl.


2019 ◽  
Author(s):  
Michael J. Strauss ◽  
Darya Asheghali ◽  
Austin Evans ◽  
Rebecca Li ◽  
Anton Chavez ◽  
...  

<p>Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length or strength of the resultant nanotubes. Imine-linked macrocycles were recently found to assemble into high-aspect ratio (>10<sup>3</sup>), lyotropic nanotubes in the presence of excess acid. Yet these harsh conditions are incompatible with many functional groups and processing methods, and lower acid loadings instead catalyze macrocycle degradation. Here we report pyridine-2,6-diimine-linked macrocycles that assemble into high-aspect ratio nanotubes in the presence of less than 1 equiv of CF<sub>3</sub>CO<sub>2</sub>H per macrocycle. Analysis by gel permeation chromatography and fluorescence spectroscopy revealed a cooperative self-assembly mechanism. Nanofibers obtained by touch-spinning the pyridinium-based nanotubes exhibit Young’s moduli of 1.48 GPa, which exceeds that of many synthetic polymers and biological filaments. These findings will enable the design of structurally diverse nanotubes from synthetically accessible macrocycles. </p>


2020 ◽  
Author(s):  
Wei-Tse Lee ◽  
Felix D. Bobbink ◽  
Antoine P. van Muyden ◽  
Kun-Han Lin ◽  
Clémence Corminboeuf ◽  
...  

RSC Advances ◽  
2021 ◽  
Vol 11 (37) ◽  
pp. 22544-22555
Author(s):  
Atefeh Safaei-Yaraziz ◽  
Shiva Akbari-Birgani ◽  
Nasser Nikfarjam

The interlacing of biopolymers and synthetic polymers is a promising strategy to fabricate hydrogel-based tissue scaffolds to biomimic a natural extracellular matrix for cell growth.


2021 ◽  
Author(s):  
Maria Nerantzaki ◽  
Capucine Loth ◽  
Jean-Francois Lutz

Nucleic acid aptamers are chemically-synthesized single-stranded oligonucleotides that fold into specific sequence-dependent configurations. Due to their exceptional recognition properties towards a variety of biological targets, they find applications in many...


2020 ◽  
Vol 4 (1) ◽  
pp. 17
Author(s):  
Aleksandra Lach ◽  
Kinga Pielichowska

Polyurethanes (PUs) are defined as a large group of synthetic polymers that contain repeated urethane linkages in their backbone. [...]


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