Configurational properties of self-interacting linear polymer chains in a three-dimensional continuum. II. Internal distributions, radius of gyration

1979 ◽  
Vol 12 (12) ◽  
pp. 2487-2495 ◽  
Author(s):  
C A Croxton
Keyword(s):  
Three Dimensional ◽  
Polymer Chains ◽  
Linear Polymer ◽  
Radius Of Gyration

scholarly journals Mechanical and Swelling Characteristics of Kappa-carrageenin/Poly-N-isopropylacrylamide Blend Hydrogels

2017 ◽  
Vol 4 (1) ◽  
pp. 61
Author(s):  
Zhang Yalong ◽  
Zhang Yanqun ◽  
Yi Min ◽  
Ha Hongfei
Keyword(s):  
Three Dimensional ◽  
Polymer Chains ◽  
Linear Polymer ◽  
Temperature Sensitive ◽  
Swelling Properties ◽  
Radiation Technology ◽  
Dimensional Network ◽  
Swelling Characteristics ◽  
Unreacted Monomer ◽  
Main Component

Two- or multi-component hydrogels consisting of the three-dimensional network of polymer chains play more and more significant role in the field of biomaterials such as contact lens, burn dressing drug delivery systems etc or in some technical fields such as gel actuators, sensors, absorbents etc. In the work, a novel blend hydrogel composed of kappa-carrageenin (KC) and polyisopropylacrylamide (PNIPAAm) was prepared via gamma-radiation technology at room temperature. The main component of the hydrogels is a typical temperature sensitive polymer PNIPAAm. As the second component, KC is a kind of natural macromolecules. The properties of the gels, such as gel strength, and swelling behavior were investigated. The incorporation of relatively small content (up to 5 wt.%) of KC could obviously improve the mechanical properties and swelling capacity. 3% KC content in the blend hydrogel is preferable for better strength and swelling properties. On the other hand, as a kind of polysaccharide, KC would be degraded by γ-rays; so<br />suitable dose must be controlled carefully. Here the total dose used was controlled below 3 kGy. KC is soluble in water. If the hydrogels synthesized in the work were as usually extracted in water or other polar solvent such as methanol, the KC in hydrogels would be also washed out completely together with unreacted monomer and linear polymer, and the action of KC in the blend hydrogels would be disappeared. Otherwise, the results published before showed that the unreacted monomer and linear polymer in the hydrogels were very small, no more than 3-5%, which would not affect the properties of the hydrogels.

Chemiluminescent self-reported unfolding of single-chain nanoparticles

2021 ◽  
Author(s):  
Fabian R. Bloesser ◽  
Sarah L. Walden ◽  
Ishrath M. Irshadeen ◽  
Lewis C. Chambers ◽  
Christopher Barner-Kowollik
Keyword(s):  
Polymer Chains ◽  
Linear Polymer ◽  
Single Chain

We demonstrate the light-induced, crosslinker mediated collapse of linear polymer chains into single-chain nanoparticles (SCNPs) capable of self-reporting their unfolding.

Novel three-dimensional long-term bone marrow culture system using polymer particles with grafted epoxy-polymer-chains supports the proliferation and differentiation of hematopoietic stem cells

2011 ◽  
Vol 236 (11) ◽  
pp. 1342-1350 ◽  
Author(s):  
Yukio Hirabayashi ◽  
Yoshihiro Hatta ◽  
Jin Takeuchi ◽  
Isao Tsuboi ◽  
Tomonori Harada ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Culture System ◽  
3D Structure ◽  
Three Dimensional ◽  
Hematopoietic Cells ◽  
3D Culture ◽  
Polymer Chains ◽  
Polymer Particles ◽  
Hematopoietic Stem ◽  
3D Culture System

Hematopoiesis occurs in the bone marrow, where primitive hematopoietic cells proliferate and differentiate in close association with a three-dimensional (3D) hematopoietic microenvironment composed of stromal cells. We examined the hematopoietic supportive ability of stromal cells in a 3D culture system using polymer particles with grafted epoxy polymer chains. Umbilical cord blood-derived CD34+ cells were co-cultivated with MS-5 stromal cells. They formed a 3D structure in the culture dish in the presence of particles, and the total numbers of cells and the numbers of hematopoietic progenitor cells, including colony-forming unit (CFU)-Mix, CFU-granulocyte-macrophage, CFU-megakaryocyte and burst-forming unit-erythroid, were measured every seven days. The hematopoietic supportive activity of the 3D culture containing polymer particles and stromal cells was superior to that of 2D culture, and allowed the expansion and maintenance of hematopoietic progenitor cells for more than 12 weeks. Various types of hematopoietic cells, including granulocytes, macrophages and megakaryocytes at different maturation stages, appeared in the 3D culture, suggesting that the CD34+ cells were able to differentiate into a range of blood cell types. Morphological examination showed that MS-5 stromal cells grew on the surface of the particles and bridged the gaps between them to form a 3D structure. Hematopoietic cells slipped into the 3D layer and proliferated within it, relying on the presence of the MS-5 cells. These results suggest that this 3D culture system using polymer particles reproduced the hematopoietic phenomenon in vitro, and might thus provide a new tool for investigating hematopoietic stem cell–stromal cell interactions.

Chemical Stress Relaxation of NR Networks Prepared in the Swollen State

1986 ◽  
Vol 59 (4) ◽  
pp. 541-550 ◽  
Author(s):  
Kyung-Do Suh ◽  
Hidetoshi Oikawa ◽  
Kenkichi Murakami
Keyword(s):  
Stress Relaxation ◽  
Network Structure ◽  
Three Dimensional ◽  
Polymer Chains ◽  
Chemical Stress ◽  
Network Chain ◽  
Crosslinking Process ◽  
Dimensional Network ◽  
Chemical Relaxation ◽  
The Difference

Abstract From the experimental results of the present investigation, it is apparent that two kinds of networks which have a different three-dimensional network structure give quite different behavior of chemical stress relaxation, even if both networks have the same network chain density. The difference in three-dimensional network structure for the two kinds of rubber arises from the degree of entanglement, which changes with the concentration of the polymer chains prior to the crosslinking process. The direct cause of chemical relaxation is due to the scission of network chains by degradation, whereas the total relaxation is caused by the change of geometrical conformation of network chains. This then casts doubt on the basic concept of chemorheology which is represented by Equation 2.

Syntheses and crystal structures of two magnesium–tetrazole compounds in salt and polymeric forms

2015 ◽  
Vol 71 (3) ◽  
pp. 222-228 ◽  
Author(s):  
Mohamed Abdellatif Bensegueni ◽  
Aouatef Cherouana ◽  
Slimane Dahaoui
Keyword(s):  
Alkaline Earth ◽  
Three Dimensional ◽  
Polymer Chains ◽  
Magnesium Ion ◽  
Water Molecules ◽  
Compound I ◽  
Hydrothermal Conditions ◽  
One Dimensional ◽  
Polymeric Chains ◽  
Hydrogen Bonded

Two alkaline earth–tetrazole compounds, namelycatena-poly[[[triaquamagnesium(II)]-μ-5,5′-(azanediyl)ditetrazolato-κ3N1,N1′:N5] hemi{bis[μ-5,5′-(azanediyl)ditetrazolato-κ3N1,N1′:N2]bis[triaquamagnesium(II)]} monohydrate], {[Mg(C2HN9)(H2O)3][Mg2(C2HN9)2(H2O)6]0.5·H2O}n, (I), and bis[5-(pyrazin-2-yl)tetrazolate] hexaaquamagnesium(II), (C5H3N6)[Mg(H2O)6], (II), have been prepared under hydrothermal conditions. Compound (I) is a mixed dimer–polymer based on magnesium ion centres and can be regarded as the first example of a magnesium–tetrazolate polymer in the crystalline form. The structure shows a complex three-dimensional hydrogen-bonded network that involves magnesium–tetrazolate dimers, solvent water molecules and one-dimensional magnesium–tetrazolate polymeric chains. The intrinsic cohesion in the polymer chains is ensured by N—H...N hydrogen bonds, which formR22(7) rings, thus reinforcing the propagation of the polymer chain along theaaxis. The crystal structure of magnesium tetrazole salt (II) reveals a mixed ribbon of hydrogen-bonded rings, of typesR22(7),R22(9) andR24(10), running along thecaxis, which are linked byR24(16) rings, generating a 4,8-cflunet.

Radius of Gyration of Polymer Chains

1962 ◽  
Vol 36 (2) ◽  
pp. 306-310 ◽  
Author(s):  
Marshall Fixman
Keyword(s):  
Polymer Chains ◽  
Radius Of Gyration

Three-Dimensional Simulation for Perikinetic Flocculation of Fine Sediment under the Ionization in Still Water

2011 ◽  
Vol 356-360 ◽  
pp. 2282-2290
Author(s):  
Lin Shuang Liu ◽  
Xin Luo ◽  
Guo Lu Yang ◽  
Ming Hui Yu
Keyword(s):  
Electrostatic Force ◽  
Three Dimensional ◽  
Fine Sediment ◽  
Radius Of Gyration ◽  
Brownian Dynamic ◽  
System A ◽  
Simulation Based ◽  
Dimensional Simulation ◽  
Original Cell ◽  
Random Variation

A simulation based on Brownian dynamic for perikinetic flocculation of fine sediment under the ionization is presented. The Langevin equation is used as dynamical equation for tracking each particle making up a floc. Monte Carlo method was used for simulate random variation in particle movement. An initial condition and periodic boundary condition which conformed to reality well is used for calculation. In each cell 1000 particles of 10𝝁 m, 15𝝁m, 20𝝁m, 25𝝁m, 30𝝁m in diameter were served as primary particles. Floc growth is based on the thermal force and the electrostatic force. The electrostatic force on a particle in the simulation cell is considered as a sum of the electrostatic force from other particles in the original cell. The particles are supposed to be motion with uncharged and charged state in dispersion system. A comparison of the initial flocculent time and smashing time in sludge density 1010kg/m3, 1025 kg/m3, 1050 kg/m3, 1075 kg/m3, 1100 kg/m3were present to show the effect of it on floc growth. The increase of sludge density deferred the flocculation rate. To study morphological shape of floc, the radius of gyration was revealed under different situations. On one hand the radius of gyration presented random variation with uncharged particle, On the other hand, the radius of gyration increases gradually with the increase of polar electrical charges on primal particle. Moreover, the morphological shape for the charged floc was more open than that of unchanged state. Finally, a series of experimental results are present, which is coincide with model well.

Pulses of Fast Electrons as a Tool To Synthesize Poly(acrylic acid) Nanogels. Intramolecular Cross-Linking of Linear Polymer Chains in Additive-Free Aqueous Solution

2003 ◽  
Vol 36 (7) ◽  
pp. 2484-2492 ◽  
Author(s):  
Slawomir Kadlubowski ◽  
Jaroslaw Grobelny ◽  
Wielislaw Olejniczak ◽  
Michal Cichomski ◽  
Piotr Ulanski
Keyword(s):  
Aqueous Solution ◽  
Acrylic Acid ◽  
Polymer Chains ◽  
Linear Polymer ◽  
Cross Linking ◽  
Fast Electrons ◽  
Poly Acrylic Acid
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