Biodegradable injectable polymer systems exhibiting a longer and controllable duration time of the gel state

2017 ◽  
Vol 5 (7) ◽  
pp. 1304-1314 ◽  
Author(s):  
Yasuyuki Yoshida ◽  
Hiroki Takai ◽  
Keisuke Kawahara ◽  
Shintaro Mitsumune ◽  
Kazuyuki Takata ◽  
...  
Keyword(s):  
Ene Reaction ◽  
Polymer Systems ◽  
Duration Time ◽  
Controllable Duration ◽  
Injectable Polymer

We report biodegradable temperature-triggered covalent gelation systems exhibiting a longer and controllable duration time of the gel state by a “mixing strategy” utilizing a thiol–ene reaction.

Extemporaneously preparative biodegradable injectable polymer systems exhibiting temperature-responsive irreversible gelation

2017 ◽  
Vol 28 (14) ◽  
pp. 1427-1443 ◽  
Author(s):  
Yasuyuki Yoshida ◽  
Kazuyuki Takata ◽  
Hiroki Takai ◽  
Keisuke Kawahara ◽  
Akinori Kuzuya ◽  
...  
Keyword(s):  
Polymer Systems ◽  
Temperature Responsive ◽  
Injectable Polymer

Structure-property relationships of PE/PP sandwiched films

1987 ◽  
Vol 45 ◽  
pp. 454-455
Author(s):  
J. Petermann ◽  
G. Broza ◽  
U. Rieck ◽  
A. Jaballah ◽  
A. Kawaguchi
Keyword(s):  
Mechanical Tests ◽  
Polymer Materials ◽  
Ionic Crystals ◽  
Structure Property ◽  
Polymer Systems ◽  
Structure Property Relationships ◽  
Oriented Films ◽  
Materials Used ◽  
Polymer Laminates ◽  
Heated Glass

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.

Techniques For The Preparation of Tissue Samples Containing Injectable Polymer Microcapsules

1985 ◽  
Vol 43 ◽  
pp. 710-711
Author(s):  
G.E. Visscher ◽  
R. L. Robison ◽  
G. J. Argentieri
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Gastrocnemius Muscle ◽  
Degradation Process ◽  
Delivery Systems ◽  
Tissue Reaction ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Injectable Polymer ◽  
Microscopic Techniques

The use of various bioerodable polymers as drug delivery systems has gained considerable interest in recent years. Among some of the shapes used as delivery systems are films, rods and microcapsules. The work presented here will deal with the techniques we have utilized for the analysis of the tissue reaction to and actual biodegradation of injectable microcapsules. This work has utilized light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic techniques. The design of our studies has utilized methodology that would; 1. best characterize the actual degradation process without artifacts introduced by fixation procedures and 2. allow for reproducible results.In our studies, the gastrocnemius muscle of the rat was chosen as the injection site. Prior to the injection of microcapsules the skin above the sites was shaved and tattooed for later recognition and recovery. 1.0 cc syringes were loaded with the desired quantity of microcapsules and the vehicle (0.5% hydroxypropylmethycellulose) drawn up. The syringes were agitated to suspend the microcapsules in the injection vehicle.

Approaches for TEM imaging of cavitation in toughened nylon

1989 ◽  
Vol 47 ◽  
pp. 352-353
Author(s):  
Barbara A. Wood
Keyword(s):  
Morphological Characteristics ◽  
Structure Property ◽  
Polymer Systems ◽  
Selective Staining ◽  
Structure Property Relationships ◽  
Rubber Toughened ◽  
Shear Yield ◽  
Controversial Topic ◽  
Selection Of ◽  
Diamond Knife

A controversial topic in the study of structure-property relationships of toughened polymer systems is the internal cavitation of toughener particles resulting from damage on impact or tensile deformation.Detailed observations of the influence of morphological characteristics such as particle size distribution on deformation mechanisms such as shear yield and cavitation could provide valuable guidance for selection of processing conditions, but TEM observation of damaged zones presents some experimental difficulties.Previously published TEM images of impact fractured toughened nylon show holes but contrast between matrix and toughener is lacking; other systems investigated have clearly shown cavitated impact modifier particles. In rubber toughened nylon, the physical characteristics of cavitated material differ from undamaged material to the extent that sectioning of heavily damaged regions by cryoultramicrotomy with a diamond knife results in sections of greater than optimum thickness (Figure 1). The detailed morphology is obscured despite selective staining of the rubber phase using the ruthenium trichloride route to ruthenium tetroxide.

Interactions between citrate and montmorillonite-Al hydroxide polymer systems

1997 ◽  
Vol 48 (3) ◽  
pp. 463-472 ◽  
Author(s):  
R.P.T. JANSSEN ◽  
M.G.M. BRUGGENWERT ◽  
W.H. VAN RIEMSDIJK
Keyword(s):  
Polymer Systems

Study on the "Tin-Ene" Reaction of α-Bromoacetophenone and Metallic Tin With Aldehydes

1996 ◽  
Vol 24 (4) ◽  
pp. 769-775
Author(s):  
Jing-Yao Zhou ◽  
Yu Jia ◽  
Qiu-Yi Shao ◽  
Shi-Hui Wu
Keyword(s):  
Ene Reaction
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