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Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday

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A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Macromolecular Chemistry".

Deadline for manuscript submissions: closed (30 June 2021) | Viewed by 42175

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Special Issue Editors

Dr. Sławomir Rubinsztajn

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Guest Editor

Centre of Molecular and Macromolecular Studies of Polish Academy of Sciences, Lodz, Poland
Interests: organosilicon chemistry; polymer chemistry; catalysis; kinetics and reaction mechanisms

Prof. Dr. Marek Cypryk

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Guest Editor

Centre of Molecular and Macromolecular Studies of Polish Academy of Sciences, Lodz, Poland
Interests: organosilicon polymer chemistry; reaction mechanisms in organometallic chemistry; computational chemistry; molecular modeling
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Wlodzimierz Stanczyk

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Centre of Molecular and Macromolecular Studies of Polish Academy of Sciences, Lodz, Poland
Interests: organosilicon chemistry; liquid crystal polymers; silsesquioxanes; nanotechnology in biomedicine

Special Issue Information

Dear Colleagues,

Professor Dr. hab. Julian Chojnowski is an outstanding chemist who has significantly contributed to the development of many fields of organosilicon chemistry and organosilicon polymer chemistry. His fundamental research in the field of kinetic and thermodynamic aspects of polymerization processes and substitution at the silicon atom has led to understanding the mechanisms of ring-opening polymerization reactions of cyclic siloxanes, as well as the discovery of the importance of inter- and intramolecular catalysis in siloxane polymerization and polycondensation processes. His expertise in the field of siloxane polymer chemistry has resulted in cooperation with the leading silicone material manufacturers such as Dow Corning and General Electric Company. His collaboration with GE resulted in the discovery of several new reactions of hydride-functional silanes and siloxanes involving activation of Si–H bond by electron-deficient boranes. Recently, he expanded his research interest into silicon-based materials. He developed the synthesis of a new class of polymers, poly(oxymultisilylene)s, and new processes leading to the synthesis of highly cross-linked polyorganosiloxane beads, which can be subsequently converted into ceramic materials.

Professor Chojnowski was born on 17 June 1935 in Warsaw, Poland. He obtained his MSc degree in chemistry from Technical University of Lodz in 1957. He carried out his graduate studies at Technical University of Lodz under the supervision of Professor Stanisław Chrzczonowicz, where he obtained his PhD in 1963. In 1966, he spent two years as a postdoctoral fellow at the University of Wisconsin–Milwaukee, USA in the research group of Professor W.W. Brandt. Upon returning to Poland, he finished his habilitation in 1971. Shortly afterwards, he moved to the newly created Centre of Molecular and Macromolecular Studies of Polish Academy of Sciences, where he became the head of the Laboratory of Heteroorganic Polymers. In 1983, he obtained the academic title of Professor of Chemistry. He retired in 2005, but he continues research at the Centre of Molecular and Macromolecular Studies as a professor emeritus. Professor J. Chojnowski is the promoter of 15 doctoral dissertations. He published about 180 original papers, 16 review papers and chapters in books, as well as several Polish and US patents. He was also a co-editor of two books. In 2005, Professor Chojnowski was awarded the Jan Zawidzki medal for outstanding achievements in the field of physical chemistry by the Polish Chemical Society. He serves as a member of the Advisory Board of Journal of Inorganic and Organometallic Polymers and Materials, Silicon (Springer), and Main Group Chemistry.

Molecules is pleased to announce a Special Issue honoring Professor Julian Chojnowski on the occasion of his 85th birthday for his outstanding achievements in silicon chemistry. This Special Issue is dedicated to all aspects of organosilicon chemistry, including silicon-based polymer chemistry, mechanistic aspects of organosilicon chemistry, and catalysis and synthesis of silicon-based materials and ceramics.

We are pleased to invite you to submit a manuscript to this Special Issue; regular articles, communications, and reviews are all welcome.

Dr. Sławomir Rubinsztajn
Prof. Marek Cypryk
Prof. Wlodzimierz Stanczyk
Guest Editors

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Keywords

Chemistry of silicon-based polymers and materials
Organosilicon chemistry
Kinetics and mechanisms of chemical reactions
Catalysis
Chemistry of silicon-based polymers and materials
Organosilicon-polymer-derived ceramic materials

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Published Papers (13 papers)

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18 pages, 4833 KiB

Open AccessArticle

Cationic Emulsion Polymerization of Octamethylcyclotetrasiloxane (D4) in Mixtures with Alkoxysilanes

by Janusz Kozakiewicz, Joanna Trzaskowska, Michał Kędzierski, Joanna Sołtysiak, Elżbieta U. Stolarczyk, Izabela Ofat-Kawalec and Jarosław Przybylski

Molecules 2022, 27(3), 605; https://doi.org/10.3390/molecules27030605 - 18 Jan 2022

Cited by 4 | Viewed by 3277

Abstract

The cationic emulsion polymerization of octamethylcyclotetrasiloxane (D4) in mixtures with methyltriethoxysilane (MTES) and vinyltriethoxysilane (VTES) was studied by FTIR ATR, GC, the development of a toluene insoluble fraction of the polymer and a gravimetric analysis. The polymerization of D4 alone was also conducted for comparison and, additionally, the development of molecular weight of polydimethylsiloxane (PDMS) obtained in that process was studied by GPC. Dodecylbenzenesulphonic acid (DBSA) was used as a surfactant and catalyst. The process was carried out in a “starved feed” mode by adding dropwise the monomer mixture to the aqueous solution of DBSA. FTIR ATR spectra were recorded by the sensor placed in the probe tip of a ReactIR 15^TM apparatus. It was found that the silicone polymer formation proceeded faster when D4 was polymerized in the mixture with alkoxysilanes, especially in the beginning of the process, and that already at the beginning of the process, the partly crosslinked polymer was formed. The induction period of ca. 30 min was observed and the concentration of cyclic siloxanes (D4 and decamethylcyclopentasiloxane—D5) remained at a very low level in the course of the reaction and only traces were detected in the final product. The particle size development in the course of the reaction was also studied and it was found that the particle size distribution was bimodal and was broadening as the reaction proceeded, though this phenomenon was less distinct when D4 was polymerized in the mixtures with alkoxysilanes. The structure of the reaction product was confirmed by ²⁹Si NMR. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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9 pages, 1534 KiB

Open AccessCommunication

Cationic Polymerization of Hexamethylcyclotrisiloxane in Excess Water

by Quentin Barnes, Claire Longuet and François Ganachaud

Molecules 2021, 26(15), 4402; https://doi.org/10.3390/molecules26154402 - 21 Jul 2021

Cited by 4 | Viewed by 2734

Abstract

Ring-opening ionic polymerization of cyclosiloxanes in dispersed media has long been discovered, and is nowadays both fundamentally studied and practically used. In this short communication, we show some preliminary results on the cationic ring-opening polymerization of hexamethylcyclotrisiloxane (D₃), a crystalline strained cycle, in water. Depending on the catalyst or/and surfactants used, polymers of various molar masses are prepared in a straightforward way. Emphasis is given here on experiments conducted with tris(pentafluorophenyl)borane (BCF), where high-molar polymers were generated at room temperature. In surfactant-free conditions, µm-sized droplets are stabilized by silanol end-groups of thus generated amphiphilic polymers, the latter of which precipitate in the course of reaction through chain extension. Introducing various surfactants in the recipe allows generating smaller emulsions in size with close polymerization ability, but better final colloidal stability, at the expense of low small cycles’ content. A tentative mechanism is finally proposed. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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13 pages, 3532 KiB

Open AccessArticle

Chlorine-Functional Silsesquioxanes (POSS-Cl) as Effective Flame Retardants and Reinforcing Additives for Rigid Polyurethane Foams

by Anna Strąkowska, Sylwia Członka, Karolina Miedzińska and Krzysztof Strzelec

Molecules 2021, 26(13), 3979; https://doi.org/10.3390/molecules26133979 - 29 Jun 2021

Cited by 9 | Viewed by 2365

Abstract

The subject of the research was the production of silsesquioxane modified rigid polyurethane (PUR) foams (POSS-Cl) with chlorine functional groups (chlorobenzyl, chloropropyl, chlorobenzylethyl) characterized by reduced flammability. The foams were prepared in a one-step additive polymerization reaction of isocyanates with polyols, and the POSS modifier was added to the reaction system in an amount of 2 wt.% polyol. The influence of POSS was analyzed by performing a series of tests, such as determination of the kinetics of foam growth, determination of apparent density, and structure analysis. Compressive strength, three-point bending strength, hardness, and shape stability at reduced and elevated temperatures were tested, and the hydrophobicity of the surface was determined. The most important measurement was the determination of the thermal stability (TGA) and the flammability of the modified systems using a cone calorimeter. The obtained results, after comparing with the results for unmodified foam, showed a large influence of POSS modifiers on the functional properties, especially thermal and fire-retardant, of the obtained PUR-POSS-Cl systems. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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14 pages, 2267 KiB

Open AccessArticle

Multiarm Star-Shaped Polydimethylsiloxanes with a Dendritic Branching Center

by Pavel A. Tikhonov, Nataliya G. Vasilenko, Marat O. Gallyamov, Georgii V. Cherkaev, Viktor G. Vasil’ev, Nina V. Demchenko, Mikhail I. Buzin, Sergey G. Vasil’ev and Aziz M. Muzafarov

Molecules 2021, 26(11), 3280; https://doi.org/10.3390/molecules26113280 - 29 May 2021

Cited by 1 | Viewed by 2393

Abstract

New multiarm stars have been synthesized based on polylithium derivatives of high-generation carbosilane dendrimers. In the synthesis of multiarm stars based on the eighth-generation dendrimer, steric hindrances were observed even during the synthesis of a polylithium initiator. Subsequently, this led to chain transfer reactions between growing arms, as well as other side effects. As a result, dense nanogel formations with a higher tendency of ordering than in classical objects of this type were isolated from the reaction mixture. The study of the rheology of multiarm stars based on sixth-generation dendrimers made it possible to determine the activation energies of viscous flow in these objects, which makes it possible to consider them as objects with a macromolecular nature and a reptation flow mechanism. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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20 pages, 5066 KiB

Open AccessArticle

An Approach to the Use of Glycol Alkoxysilane–Polysaccharide Hybrids in the Conservation of Historical Building Stones

by Miguel Meléndez-Zamudio, Ileana Bravo-Flores, Eulalia Ramírez-Oliva, Antonio Guerra-Contreras, Gilberto Álvarez-Guzmán, Ramón Zárraga-Nuñez, Antonio Villegas, Merced Martínez-Rosales and Jorge Cervantes

Molecules 2021, 26(4), 938; https://doi.org/10.3390/molecules26040938 - 10 Feb 2021

Cited by 4 | Viewed by 2352

Abstract

Stone consolidants have been widely used to protect historical monuments. Consolidants and hydrophobic formulations based on the use of tetraethoxysilane (TEOS) and alkylalkoxysilanes as precursors have been widely applied, despite their lack of solubility in water and requirement to be applied in organic media. In the search for a “greener” alternative based on silicon that has potential use in this field, the use of tetrakis(2-hydroxyethyl)silane (THEOS) and tris(2-hydroxyethyl)methyl silane (MeTHEOS) as precursors, due their high water solubility and stability, is proposed in this paper. It is already known that THEOS and MeTHEOS possess remarkable compatibility with different natural polysaccharides. The investigated approach uses the water-soluble silanes THEOS–chitosan and MeTHEOS–chitosan as a basis for obtaining hybrid consolidants and hydrophobic formulations for the conservation of siliceous and calcareous stones. In the case of calcareous systems, their incompatibility with alkoxysilanes is known and is expected to be solved by the developed hybrid consolidant. Their application in the conservation of building stones from historical and archeological sites from Guanajuato, México was studied. The evaluation of the consolidant and hydrophobic formulation treatment was mainly conducted by determining the mechanical properties and contact angle measurements with satisfactory results in terms of the performance and compatibility with the studied stones. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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16 pages, 4028 KiB

Open AccessArticle

New Antiadhesive Hydrophobic Polysiloxanes

by Maria Nowacka, Anna Rygała, Dorota Kręgiel and Anna Kowalewska

Molecules 2021, 26(4), 814; https://doi.org/10.3390/molecules26040814 - 4 Feb 2021

Cited by 8 | Viewed by 2398

Abstract

Intrinsic hydrophobicity is the reason for efficient bacterial settlement and biofilm growth on silicone materials. Those unwelcomed phenomena may play an important role in pathogen transmission. We have proposed an approach towards the development of new anti-biofilm strategies that resulted in novel antimicrobial hydrophobic silicones. Those functionalized polysiloxanes grafted with side 2-(carboxymethylthioethyl)-, 2-(n-propylamidomethylthioethyl)- and 2-(mercaptoethylamidomethylthioethyl)- groups showed a wide range of antimicrobial properties towards selected strains of bacteria (reference strains Staphylococcus aureus, Escherichia coli and water-borne isolates Agrobacterium tumefaciens, Aeromonas hydrophila), fungi (Aureobasidium pullulans) and algae (Chlorella vulgaris), which makes them valuable antibacterial and antibiofilm agents. Tested microorganisms showed various levels of biofilm formation, but particularly effective antibiofilm activity was demonstrated for bacterial isolate A. hydrophila with high adhesion abilities. In the case of modified surfaces, the relative coefficient of adhesion for this strain was 18 times lower in comparison to the control glass sample. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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15 pages, 12891 KiB

Open AccessArticle

Synthesis of Silsesquioxanes with Substituted Triazole Ring Functionalities and Their Coordination Ability

by Monika Rzonsowska, Katarzyna Kozakiewicz, Katarzyna Mituła, Julia Duszczak, Maciej Kubicki and Beata Dudziec

Molecules 2021, 26(2), 439; https://doi.org/10.3390/molecules26020439 - 15 Jan 2021

Cited by 4 | Viewed by 2679

Abstract

A synthesis of a series of mono-T₈ and difunctionalized double-decker silsesquioxanes bearing substituted triazole ring(s) has been reported within this work. The catalytic protocol for their formation is based on the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) process. Diverse alkynes were in the scope of our interest—i.e., aryl, hetaryl, alkyl, silyl, or germyl—and the latter was shown to be the first example of terminal germane alkyne which is reactive in the applied process’ conditions. From the pallet of 15 compounds, three of them with pyridine-triazole and thiophenyl-triazole moiety attached to T₈ or DDSQ core were verified in terms of their coordinating properties towards selected transition metals, i.e., Pd(II), Pt(II), and Rh(I). The studies resulted in the formation of four SQs based coordination compounds that were obtained in high yields up to 93% and their thorough spectroscopic characterization is presented. To our knowledge, this is the first example of the DDSQ-based molecular complex possessing bidentate pyridine-triazole ligand binding two Pd(II) ions. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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15 pages, 1761 KiB

Open AccessFeature PaperArticle

Controlled Synthesis of Polyphosphazenes with Chain-Capping Agents

by Robert A. Montague and Krzysztof Matyjaszewski

Molecules 2021, 26(2), 322; https://doi.org/10.3390/molecules26020322 - 10 Jan 2021

Cited by 3 | Viewed by 3105

Abstract

N-alkyl phosphoranimines were synthesized via the Staudinger reaction of four different alkyl azides with tris(2,2,2-trifluoroethyl) phosphite. N-adamantyl, N-benzyl, N-t-butyl, and N-trityl phosphoranimines were thoroughly characterized and evaluated as chain-capping compounds in the anionic polymerization of P-tris(2,2,2-trifluoroethoxy)-N-trimethylsilyl phosphoranimine monomer. All four compounds reacted with the active chain ends in a bulk polymerization, and the alkyl end groups were identified by ¹H-NMR spectroscopy. These compounds effectively controlled the molecular weight of the resulting polyphosphazenes. The chain transfer constants for the monomer and N-benzyl phosphoranimine were determined using Mayo equation. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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14 pages, 2603 KiB

Open AccessCommunication

When Attempting Chain Extension, Even Without Solvent, It Is Not Possible to Avoid Chojnowski Metathesis Giving D₃

by Mengchen Liao, Yang Chen and Michael A. Brook

Molecules 2021, 26(1), 231; https://doi.org/10.3390/molecules26010231 - 5 Jan 2021

Cited by 3 | Viewed by 2587

Abstract

A simple, mild and efficient method to prepare HSi- or HOSi-telechelic, high-molecular-weight polydimethylsiloxane polymers (to 41,600 g·mol⁻¹) using the one-shot hydrolysis of M^HM^H is reported; titration of the water allowed for higher molecular weights (to 153,900 g·mol⁻¹). The “living” character of the chain extension processes was demonstrated by adding a small portion of M^HM^H and B(C₆F₅)₃ (BCF) to a first formed polymer, which led to a ~2-fold, second growth in molecular weight. The heterogeneous reaction reached completion in less than 30 min, much less in some cases, regardless of whether it was performed neat or 50 wt% in dry toluene; homogeneous reactions in toluene were much slower. The process does not involve traditional redistribution, as judged by the low quantities (<3%) of D₄ produced. However, it is not possible to avoid Chojnowski metathesis from M^HDDM^H giving D₃, which occurs competitively with chain extension. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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21 pages, 16607 KiB

Open AccessArticle

Reliable Condensation Curing Silicone Elastomers with Tailorable Properties

by Alena Jurásková, Stefan Møller Olsen, Kim Dam-Johansen, Michael A. Brook and Anne Ladegaard Skov

Molecules 2021, 26(1), 82; https://doi.org/10.3390/molecules26010082 - 27 Dec 2020

Cited by 9 | Viewed by 5251

Abstract

The long-term stability of condensation curing silicone elastomers can be affected by many factors such as curing environment, cross-linker type and concentration, and catalyst concentration. Mechanically unstable silicone elastomers may lead to undesirable application failure or reduced lifetime. This study investigates the stability of different condensation curing silicone elastomer compositions. Elastomers are prepared via the reaction of telechelic silanol-terminated polydimethylsiloxane (HO-PDMS-OH) with trimethoxysilane-terminated polysiloxane ((MeO)₃Si-PDMS-Si(OMe)₃) and ethoxy-terminated octakis(dimethylsiloxy)-T8-silsesquioxane ((QM^OEt)₈), respectively. Two post-curing reactions are found to significantly affect both the stability of mechanical properties over time and final properties of the resulting elastomers: Namely, the condensation of dangling and/or unreacted polymer chains, and the reaction between cross-linker molecules. Findings from the stability study are then used to prepare reliable silicone elastomer coatings. Coating properties are tailored by varying the cross-linker molecular weight, type, and concentration. Finally, it is shown that, by proper choice of all three parameters, a coating with excellent scratch resistance and electrical breakdown strength can be produced even without an addition of fillers. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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15 pages, 4306 KiB

Open AccessFeature PaperArticle

Novel Polyhedral Silsesquioxanes [POSS(OH)₃₂] as Anthracycline Nanocarriers—Potential Anticancer Prodrugs

by Kinga Piorecka, Jan Kurjata and Wlodzimierz A. Stanczyk

Molecules 2021, 26(1), 47; https://doi.org/10.3390/molecules26010047 - 24 Dec 2020

Cited by 5 | Viewed by 2273

Abstract

Anthracyclines belong to the anticancer drugs that are widely used in chemotherapy. However, due to their systemic toxicity they also exert dangerous side effects associated mainly with cardiovascular risks. The pathway that is currently often developed is their chemical and physical modification via formation of conjugated or complexed prodrug systems with a variety of nanocarriers that can selectively release the active species in cancer cells. In this study, six new nanoconjugates were synthesized with the use of polyhedral oligosilsesquioxanes [POSS(OH)₃₂] as nanocarriers of the anticancer drugs anthracyclines—doxorubicin (DOX) and daunorubicin (DAU). These prodrug conjugates are also equipped with poly(ethylene glycol) (PEG) moieties of different structure and molecular weight. Water-soluble POSS, succinic anhydride modified (SAMDOX and SAMDAU) with carboxylic function, and PEGs (PEG1, PEG2 and PEGB3) were used for the synthesis. New nanoconjugates were formed via ester bonds and their structure was confirmed by NMR spectroscopy (¹H-NMR, ¹³C-NMR, ¹H-¹³C HSQC, DOSY and ¹H-¹H COSY), FTIR and DLS. Drug release rate was evaluated using UV-Vis spectroscopy at pH of 5.5. Release profiles of anthracyclines from conjugates 4–9 point to a range of 10 to 75% (after 42 h). Additionally, model NMR tests as well as diffusion ordered spectroscopy (DOSY) confirmed formation of the relevant prodrugs. The POSS-anthracycline conjugates exhibited prolonged active drug release time that can lead to the possibility of lowering administered doses and thus giving them high potential in chemotherapy. Drug release from conjugate 7 after 42 h was approx. 10%, 33% for conjugate 4, 47% for conjugate 5, 6, 8 and 75% for conjugate 9. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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20 pages, 12318 KiB

Open AccessArticle

Limonene Derivative of Spherosilicate as a Polylactide Modifier for Applications in 3D Printing Technology

by Dariusz Brząkalski, Bogna Sztorch, Miłosz Frydrych, Daria Pakuła, Kamil Dydek, Rafał Kozera, Anna Boczkowska, Bogdan Marciniec and Robert E. Przekop

Molecules 2020, 25(24), 5882; https://doi.org/10.3390/molecules25245882 - 12 Dec 2020

Cited by 16 | Viewed by 3571

Abstract

The first report of using limonene derivative of a spherosilicate as a modifier of polylactide used for 3D printing and injection moulding is presented. The paper presents the use of limonene-functionalized spherosilicate derivative as a functional additive. The study compared the material characteristics of polylactide modified with SS-Limonene (0.25–5.0% w/w) processed with traditional injection moulding and 3D printing (FFF, FDM). A significant improvement in the processing properties concerning rheology, inter-layer adhesion, and mechanical properties was achieved, which translated into the quality of the print and reduction of waste production. Moreover, the paper describes the elementary stages of thermal transformations of the obtained hybrid systems. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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44 pages, 30111 KiB

Open AccessReview

Applications of Hybrid Polymers Generated from Living Anionic Ring Opening Polymerization

by Jonathan Goff, Santy Sulaiman and Barry Arkles

Molecules 2021, 26(9), 2755; https://doi.org/10.3390/molecules26092755 - 7 May 2021

Cited by 18 | Viewed by 5701

Abstract

Increasingly precise control of polymer architectures generated by “Living” Anionic Ring-Opening Polymerization (Living AROP) is leading to a broad range of commercial advanced material applications, particularly in the area of siloxane macromers. While academic reports on such materials remain sparse, a significant portion of the global population interacts with them on a daily basis—in applications including medical devices, microelectronics, food packaging, synthetic leather, release coatings, and pigment dispersions. The primary driver of this increased utilization of siloxane macromers is their ability to incorporate the properties of silicones into organic structures in a balanced manner. Compared to organic polymers, the differentiating properties of silicones—low T_g, hydrophobicity, low surface energy, and high free molal space—logically lend themselves to applications in which low modulus, release, permeability to oxygen and moisture, and tactile interaction are desired. However, their mechanical, structural and processing properties have until recently precluded practical applications. This review presents applications of “Living” AROP derived polymers from the perspective of historical technology development. Applications in which products are produced on a commercial scale—defined as not only offered for sale, but sold on a recurrent basis—are emphasized. Hybrid polymers with intriguing nanoscale morphology and potential applications in photoresist, microcontact printing, biomimetic soft materials, and liquid crystals are also discussed. Previously unreported work by the authors is provided in the context of this review. Full article

(This article belongs to the Special Issue Various Aspects of Silicon Polymer Chemistry: A Themed Issue in Honor of Professor Julian Chojnowski on the Occasion of His 85th Birthday)

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