scholarly journals Inside Cover: High Degree of Polymerization in a Fullerene-Containing Supramolecular Polymer (Angew. Chem. Int. Ed. 22/2014)

2014 ◽  
Vol 53 (22) ◽  
pp. 5476-5476
Author(s):  
Helena Isla ◽  
Emilio M. Pérez ◽  
Nazario Martín
Keyword(s):  
Degree Of Polymerization ◽  
Supramolecular Polymer ◽  
High Degree

High Degree of Polymerization in a Fullerene-Containing Supramolecular Polymer

2014 ◽  
Vol 126 (22) ◽  
pp. 5735-5739 ◽  
Author(s):  
Helena Isla ◽  
Emilio M. Pérez ◽  
Nazario Martín
Keyword(s):  
Degree Of Polymerization ◽  
Supramolecular Polymer ◽  
High Degree

High Degree of Polymerization in a Fullerene-Containing Supramolecular Polymer

2014 ◽  
Vol 53 (22) ◽  
pp. 5629-5633 ◽  
Author(s):  
Helena Isla ◽  
Emilio M. Pérez ◽  
Nazario Martín
Keyword(s):  
Degree Of Polymerization ◽  
Supramolecular Polymer ◽  
High Degree

scholarly journals Oriented arrangement of simple monomers enabled by confinement: towards living supramolecular polymerization

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yingtong Zong ◽  
Si-Min Xu ◽  
Wenying Shi ◽  
Chao Lu
Keyword(s):  
Activation Barrier ◽  
Degree Of Polymerization ◽  
Supramolecular Polymer ◽  
Energy Principle ◽  
Spontaneous Nucleation ◽  
Pyrene Derivatives ◽  
Multifunctional Molecules ◽  
Double Hydroxide ◽  
Supramolecular Polymerization ◽  
Kinetics Of

AbstractThe living supramolecular polymerization technique provides an exciting research avenue. However, in comparison with the thermodynamic spontaneous nucleation, using simple monomers to realize living supramolecular polymerization is hardly possible from an energy principle. This is because the activation barrier of kinetically trapped simple monomer (nucleation step) is insufficiently high to control the kinetics of subsequent elongation. Here, with the benefit of the confinement from the layered double hydroxide (LDH) nanomaterial, various simple monomers, (such as benzene, naphthalene and pyrene derivatives) successfully form living supramolecular polymer (LSP) with length control and narrow dispersity. The degree of polymerization can reach ~6000. Kinetics studies reveal LDH overcomes a huge energy barrier to inhibit undesired spontaneous nucleation of monomers and disassembly of metastable states. The universality of this strategy will usher exploration into other multifunctional molecules and promote the development of functional LSP.

scholarly journals Use of Electrosprayed Agave Fructans as Nanoencapsulating Hydrocolloids for Bioactives

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 868 ◽  
Author(s):  
Jorge Ramos-Hernández ◽  
Juan Ragazzo-Sánchez ◽  
Montserrat Calderón-Santoyo ◽  
Rosa Ortiz-Basurto ◽  
Cristina Prieto ◽  
...  
Keyword(s):  
Uv Light ◽  
Particle Morphology ◽  
Bioactive Compound ◽  
Processing Parameters ◽  
Degree Of Polymerization ◽  
Spherical Particles ◽  
Sem Images ◽  
High Degree ◽  
Thermal Stability Of ◽  
Β Carotene

High degree of polymerization Agave fructans (HDPAF) are presented as a novel encapsulating material. Electrospraying coating (EC) was selected as the encapsulation technique and β-carotene as the model bioactive compound. For direct electrospraying, two encapsulation methodologies (solution and emulsion) were proposed to find the formulation which provided a suitable particle morphology and an adequate concentration of β-carotene encapsulated in the particles to provide a protective effect of β-carotene by the nanocapsules. Scanning electron microscopy (SEM) images showed spherical particles with sizes ranging from 440 nm to 880 nm depending on the concentration of HDPAF and processing parameters. FTIR analysis confirmed the interaction and encapsulation of β-carotene with HDPAF. The thermal stability of β-carotene encapsulated in HDPAF was evidenced by thermogravimetric analysis (TGA). The study showed that β-carotene encapsulated in HDPAF by the EC method remained stable for up to 50 h of exposure to ultraviolet (UV) light. Therefore, HDPAF is a viable option to formulate nanocapsules as a new encapsulating material. In addition, EC allowed for increases in the ratio of β-carotene:polymer, as well as its photostability.

Acetylation of Bacterial Cellulose: Preparation of Cellulose Acetate Having a High Degree of Polymerization

1998 ◽  
Vol 62 (7) ◽  
pp. 1451-1454 ◽  
Author(s):  
Mari TABUCHI ◽  
Kunihiko WATANABE ◽  
Yasushi MORINAGA ◽  
Fumihiro YOSHINAGA
Keyword(s):  
Cellulose Acetate ◽  
Bacterial Cellulose ◽  
Degree Of Polymerization ◽  
High Degree

scholarly journals Anatomy and fructan distribution in vegetative organs of Dimerostemma vestitum (Asteraceae) from the campos rupestres

2015 ◽  
Vol 87 (2) ◽  
pp. 797-812 ◽  
Author(s):  
Taiza M. Silva ◽  
Divina A.A. Vilhalva ◽  
Moemy G. Moraes ◽  
Rita de Cássia L. Figueiredo-Ribeiro
Keyword(s):  
Glandular Trichomes ◽  
Polarized Light ◽  
Degree Of Polymerization ◽  
Campos Rupestres ◽  
Water Restriction ◽  
Secretory Structures ◽  
Vegetative Organs ◽  
Semi Arid Region ◽  
Aerial Stem ◽  
High Degree

Among the compounds stored by plants, several functions are assigned to fructans, such as source of energy and protection against drought and extreme temperatures. In the present study we analyzed the anatomy and distribution of fructans in vegetative organs of Dimerostemma vestitum (Asteraceae), an endemic species from the Brazilian campos rupestres. D. vestitum has amphistomatic and pubescent leaves, with both glandular and non-glandular trichomes. In the basal aerial stem the medulla has two types of parenchyma, which differ from the apical portion. The xylopodium has mixed anatomical origin. Interestingly, although inulin-type fructans with high degree of polymerization were found in all analyzed organs except the leaves, the highest amount and maximum degree of polymerization were detected in the xylopodium. Inulin sphero-crystals were visualized under polarized light in the medulla and in the vascular tissues mainly in the central region of the xylopodium, which has abundant xylem parenchyma. Secretory structures accumulating several compounds but not inulin were identified within all the vegetative organs. The presence of these compounds, in addition to inulin, might be related to the strategies of plants to survive adverse conditions in a semi-arid region, affected seasonally by water restriction and frequently by fire.

Glass Hydration Mechanisms with Application to Obsidian Hydration Dating

1988 ◽  
Vol 123 ◽  
Author(s):  
William B. White
Keyword(s):  
Infrared Spectroscopy ◽  
Three Dimensional ◽  
Depth Profiling ◽  
Structural Disorder ◽  
Degree Of Polymerization ◽  
Concentration Profiles ◽  
Surface Layers ◽  
Profiling Techniques ◽  
High Degree ◽  
Depth Concentration

AbstractChemical analysis of typical obsidians place them with a group of silica- and alumina-rich glasses constructed of a three dimensional framework of silica and alumina tetrahedra with nearly all tetrahedra sharing corners. Raman and infrared spectra of unweathered obsidians confirm the high degree of polymerization as well as some additional structural disorder. Analysis of dissolution rates of various glasses shows obsidian to be among the most stable, comparable to the most durable synthetic glasses. Surface layers on glasses can be chemically characterized by depth-profiling techniques such as SIMS and SIPS that give depth-concentration profiles for individual elements. Hydration rinds on glasses can be structurally characterized by infrared spectroscopy which shows both hydration and re-polymerization as the rinds age. Because obsidians are already completely polymerized glasses, their hydration rinds are mainly a result of hydrolysis and alkali exchange.

Germplasm evaluation to obtain inulin with high degree of polymerization in Mediterranean environment

2019 ◽  
Vol 34 (1) ◽  
pp. 187-191 ◽  
Author(s):  
M.G. Melilli ◽  
F. Branca ◽  
C. Sillitti ◽  
S. Scandurra ◽  
P. Calderaro ◽  
...  
Keyword(s):  
Degree Of Polymerization ◽  
Germplasm Evaluation ◽  
Mediterranean Environment ◽  
High Degree
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