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Polyurethane
Published in Narendra Pal Singh Chauhan, Functionalized Polymers, 2021
Noushin Ezzati, Ebad Asadi, Majid Abdouss, Elaheh Kowsari
Polyurethanes that are easy to prepare and have other special characteristics are suitable for preparation of supramolecular structures (Houton et al. 2015). Preparation of supramolecular polymer networks was proposed according to non-covalent interactions (Voorhaar and Hoogenboom 2016). In such supramolecular polymers, the low-energy bonding of non-covalent bonds such as metal coordination, host-guest complexation, hydrogen bonding, π-π staking, and electrostatic interaction can provide a wide range of unique characteristics such as better processability and self-healing behavior (Comí et al. 2017).
Characteristics of Polymers and Polymerization Processes
Published in Manas Chanda, Plastics Technology Handbook, 2017
Supramolecular polymers are a relatively new class of polymers in which monomeric repeating units are held together with directional and reversible (noncovalent) secondary interactions, unlike conventional macromolecular species in which repetition of monomeric units is mainly governed by covalent bonding. A schematic comparison of a covalent polymer and a supramolecular polymer is shown in Figure 1.22.
Hydrogen Bonded SupramolecularPolymers versus Wormlike Micelles
Published in Raoul Zana, Eric W. Kaler, Giant Micelles, 2007
In suitable conditions, both wormlike micelles and supramolecular polymers form long reversible chains with similar rheological properties, but there is a most significant difference between them. Supramolecular polymers self-assemble because the monomer contains specific and directional complementary associating groups. In fact, the structure of the monomer can be understood as made of two independent parts: the associating groups, which are responsible for the self-assembly process, and the rest of the molecule, which can be altered nearly at will without compromising the self-assembly (as long as no interfering hydrogen bonding groups are introduced). Consequently, it is possible to tune the properties and to add functionality through chemical design. In contrast, wormlike micelles form because of the overall structure of the monomer (surfactant): the relevant parameter is the packing parameter measuring the balance between the hydro-phobic tail, the polar head group, and the counterion. Introducing a new chemical group in one part of the surfactant may tilt the delicate balance and thus completely change the topology of the micelle. The following characteristics of supramolecular polymers illustrate this point. Some of the properties described here can also be obtained in the case of wormlike micelles, but the specificity of supramolecular polymers is the direct relationship between the chemical structure and the properties.
Supramolecular sulfur-containing polymers with hydrogen bonding
Published in Journal of Sulfur Chemistry, 2023
Yuichiro Kobayashi, Yuki Yamagishi, Ryuto Nishimura, Chun-Lin Xiao, Daiki Kitano, Akiyoshi Horiguchi, Shun Hashimoto, Hiroyasu Yamaguchi
In this research, we report a new methodology to synthesize a polysulfide polymer via a supramolecular chemistry approach. For this purpose, we focused on supramolecular polymers, which were prepared by connecting monomers with each other through non-covalent bonds [18-21]. Unlike ordinary polymers formed from covalent bonds, supramolecular polymers exhibit reversible formation and dissociation. Consequently, they are suitable for a wide range of applications, including self-healing materials, stimuli-responsive materials, and catalysts [22-26]. Supramolecular formation of sulfur-containing polymers may give functional supramolecular sulfur-containing polymers [27,28]. Herein, we prepare a sulfur-containing organic compound with hydrogen bonding unit, 2-ureido-4[1H]pyrimidinone (UPy), at both ends to give a main-chain type supramolecular sulfur-containing polymers (poly(LS-UPy)) (Figure 1).
From small molecules to polymeric probes: recent advancements of formaldehyde sensors
Published in Science and Technology of Advanced Materials, 2022
Swagata Pan, Subhadip Roy, Neha Choudhury, Priyanka Priyadarshini Behera, Kannan Sivaprakasam, Latha Ramakrishnan, Priyadarsi De
In recent years, water-soluble supramolecular polymers have gained significant attention due to their potential biomedical applications. Looking into these aspects for selective detection of FA, Fan and co-workers have reported a water-soluble supramolecular polymer (Probe 16, Figure 6(a)) using a compound as N1,N3,N5-tri(pyridin-4-yl)benzene-1,3,5-tricarboxamide (DTA) [78] (Table 2). The addition of FA solution into DTA resulted in supramolecular self-assembly in water through hydrogen bonding interaction (Figure 6(a)). When several aldehydes were added to DTA, only in the case of FA, the state of DTA changed to a colorless solution and a light blue fluorescence was observed under UV light (λem = 470 nm) (Figure 6(b)). Moreover, a morphological change to fiber structure was noticed after FA addition as confirmed by Scanning Electron Microscopy (SEM) analysis (Figure 6(c)). The LOD of DTA for FA was calculated to be 1.79 × 10−8 M.
Acetyl-protected cytosine and guanine containing acrylics as supramolecular adhesives
Published in The Journal of Adhesion, 2019
Keren Zhang, Gregory B Fahs, Evan Margaretta, Amanda G Hudson, Robert B Moore, Timothy E. Long
Supramolecular polymers often refer to polymers that contain noncovalent interactions such as hydrogen bonding, π-π stacking, and electrostatic interactions.[1–4] These noncovalent interactions with intermediate bond strengths that are stronger than van der Waals interaction but weaker than chemical bonds afford physically crosslinked supramolecular networks. These robust and reversible associations provide various advantages over chemical crosslinking. For example, hydrogen bonding increases apparent molecular weight and drives self-assembly of supramolecular polymers, resulting in enhanced mechanical performance and processability,[5–8] ordered morphologies,[9–15] and stimuli-responsiveness to external triggers.[16,17] These unique properties of supramolecular polymers enable applications in a wide variety of forefront technologies as self-healing and mendable materials,[18–20] polymerization templates,[21,22] and nanomaterials.[10,11,23,24] In addition, formulation of adhesives, elastomers, additives, coatings, surfactants, and adsorbents commonly utilizes physically crosslinked polymers with tunable physical properties to achieve desirable performance.[1,8,25–31]