A New Hydrocarbon Elastomer. I. Copolymerization of Olefins and Nonconjugated Dienes

1962 ◽  
Vol 35 (4) ◽  
pp. 1114-1125 ◽  
Author(s):  
E. K. Gladding ◽  
B. S. Fisher ◽  
J. W. Collette
Keyword(s):  
Oxidative Stability ◽  
Polymer Synthesis ◽  
Laboratory Scale ◽  
Polymer Composition ◽  
Polymerization Temperature ◽  
General Terms ◽  
Polymer Formation ◽  
Polymer Properties ◽  
Catalyst Type

Abstract The composition of sulfur-curable elastomers derived from olefins and diolefins is described and methods are given for their synthesis using coordination catalysts. Certain factors that influence the laboratory-scale polymer synthesis are discussed and the effects of catalyst type, polymerization temperature, and diene structure on the rate of polymer formation and polymer composition are outlined. Polymer properties are discussed in general terms, with particular emphasis on oxidative stability.

scholarly journals Evaluation of Polymeric Materials for Chemical Enhanced Oil Recovery

Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 361 ◽  
Author(s):  
Alison J. Scott ◽  
Laura Romero-Zerón ◽  
Alexander Penlidis
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Polymeric Materials ◽  
Polymer Flooding ◽  
Chemical Degradation ◽  
Polymer Composition ◽  
General Terms ◽  
Polymer Properties ◽  
Application Specific ◽  
Evaluation Techniques

Polymer flooding is a promising enhanced oil recovery (EOR) technique; sweeping a reservoir with a dilute polymer solution can significantly improve the overall oil recovery. In this overview, polymeric materials for enhanced oil recovery are described in general terms, with specific emphasis on desirable characteristics for the application. Application-specific properties should be considered when selecting or developing polymers for enhanced oil recovery and should be carefully evaluated. Characterization techniques should be informed by current best practices; several are described herein. Evaluation of fundamental polymer properties (including polymer composition, microstructure, and molecular weight averages); resistance to shear/thermal/chemical degradation; and salinity/hardness compatibility are discussed. Finally, evaluation techniques to establish the polymer flooding performance of candidate EOR materials are described.

Carcass Tear Out Load Model for Multi-Layer Pressure Sheath Risers

2014 ◽  
Author(s):  
Claus Egebjerg Kristensen ◽  
Jan Muren ◽  
Geir Skeie ◽  
Håvard Skjerve ◽  
Nils Sødahl
Keyword(s):  
Probability Of Failure ◽  
Simulation Approach ◽  
Axial Loads ◽  
Contributing Factors ◽  
Load Model ◽  
General Terms ◽  
Polymer Properties ◽  
Flexible Risers ◽  
Key Driver ◽  
Gravity Component

Recent failures of multi-layer pressure sheath risers have shown that the carcass may fail in the top termination due to excessive axial loads. This is a new failure mode for flexible risers, recently presented by the authors in more general terms. The present paper explains details of the established load model and the validation against mid-scale tests, risers failed during operation, and operating risers close to failure by this new mode. The key driver in the model is the temperature contraction of pressure sheath layers. Also influenced by changes in polymer properties over the operational history, temperature and time is explained. Other contributing factors in the load model are gravity-component and bore pressure. The prediction model for the carcass loads are developed during Statoils investigation in 2011–12. The model is regarded representative for 20% of the most exposed risers. Several of the input parameters are uncertain and a Monte Carlo simulation approach is selected to study the variability and predict the probability of failure, given that radial contact pressure is sufficiently low. The approach adopted in the model may be applicable to other risers where polymers and steel components act together, and in such circumstances act as a guide for alternative model developments.

Diazo-Initiated Polymers. Preparation, Properties, and Evaluation

1954 ◽  
Vol 27 (1) ◽  
pp. 88-103
Author(s):  
J. M. Willis ◽  
Glen Alliger ◽  
B. L. Johnson ◽  
W. M. Otto
Keyword(s):  
Great Majority ◽  
Synthetic Polymers ◽  
Water Soluble ◽  
Diazo Compounds ◽  
Polymerization Temperature ◽  
Synthetic Rubber ◽  
Polymer Properties ◽  
Rate Of Polymerization ◽  
The Many ◽  
Preparation And Evaluation

Abstract Throughout the great majority of the many investigations on rubberlike synthetic polymers, the initiators employed have been peroxides, either water-soluble (potassium persulfate being the chief example) or oil-soluble, such as benzoyl peroxide or diisopropylbenzene monohydroperoxide. The most notable departure from these initiators has been the use of the diazothio ethers, 4-methoxybenzenediazomercapto-2-naphthalene (MDN) and 4-methylbenzenediazomercapto-2-naphthalene (TDN). These materials have proved to be suitable initiators and also to have some activity as modifiers. However, their possibilities have been explored principally at a polymerization temperature of 41° F. Thus, the field of initiators has been subject to less widespread investigation than most of the other variables in a typical synthetic rubber recipe. The purpose of the present investigation was to develop different initiators, if possible, of a type which would lead to improvement of polymer structure at 122° F. It was felt from the outset that diazo-type compounds offered the best possibilities for development along these lines. During a preliminary survey of these materials, the object was to find examples which did not have the two disadvantages of the diazothio ethers—high cost and low stability. The use of diazo-type compounds as polymerization initiators has been known for many years. The work of Buizov on the polymerization of butadiene with diazoaminobenzene is an example of this. A number of patents have been issued relating to the use of diazo compounds in general as polymerization initiators or activators. These patents, however, were directed toward improving the rate of polymerization, and did not indicate any outstanding improvement in polymer properties. After detailed study of the properties and reactions of diazo materials in general, stabilized salts of diazotized aromatic amines were selected as the specific type of compound with the greatest chance of success. The program was begun with the laboratory preparation and evaluation of diazo salts.

Thermoplastic Polyurethane Elastomer Melt Polymerization Study

1982 ◽  
Vol 55 (1) ◽  
pp. 137-150 ◽  
Author(s):  
C. S. Schollenberger ◽  
K. Dinbergs ◽  
F. D. Stewart
Keyword(s):  
Molecular Weight ◽  
Thermoplastic Polyurethane ◽  
Degree Of Polymerization ◽  
Virtual Network ◽  
Polymer Composition ◽  
Polymerization Temperature ◽  
Quiescent State ◽  
Polyurethane Elastomer ◽  
Melt Polymerization ◽  
Thermoplastic Polyurethane Elastomer

Abstract It is concluded from the present study that the slightly modified Brabender PlastiCorder torque rheometer is well suited to the study of thermoplastic polyurethane elastomer melt polymerization. The instrument is sensitive and responsive enough over a broad range to sense and record continuously even small changes in polymerizate temperature and viscosity as a function of time. This capability has enabled us to follow the full course of such polymerizations, with the exception of the final polymer maturation process which customarily is effected in the quiescent state. In our study, the effects of several polymerization variables were clearly and quantitatively apparent, including the effects on the course of polymerization and its degree of: macroglycol acidity; antioxidant (stabilizer); temperature; catalyst; polymer composition; presence of shortstop; and reactant balance. The results demonstrate the known acid catalysis of the hydroxyl-isocyanate reaction as well as polyurethane molecular weight modification by polyester glycol acidity. The inclusion of a commercial phenolic antioxidant in the polymerization charge did not have any obvious effect on the course of polymerization but may have limited degree of polymerization somewhat. Increased urethane content greatly speeds the viscosity increase, demonstrating urethane autocatalysis as well as its viscosity contribution, and even low stannous octoate catalyst levels appreciably speeded the inherently rapid polymerization. The shortstopping action of fugitive and persistent primary alcohols is prompt and effective, but excessive amounts produce some irreversible polymer reversion as they readjust the polymer chain molecular weight distribution present in maintaining the urethane equilibrium. This equilbrium also showed clear response to polymerization temperature, reversible urethane dissociation reducing viscosity with increasing temperature. The effect of polymerization reactant imbalance was readily apparent in the appreciably reduced rate and degree of polymerization attending minor isocyanate deficiency. Mastication experiments in the PlastiCorder show dried preformed polyurethane elastomer to drop quickly to viscosity levels much below that reached by the same compositions during polymer formation. The viscosity loss of the former is attributed to polyurethane chain rupture promoted by virtual network restrictions to chain slippage, while the virtual network has not yet developed in the forming polymer.

Star polymer synthesis via λ-orthogonal photochemistry

2016 ◽  
Vol 52 (60) ◽  
pp. 9426-9429 ◽  
Author(s):  
Kai Hiltebrandt ◽  
Michael Kaupp ◽  
Edgar Molle ◽  
Jan P. Menzel ◽  
James P. Blinco ◽  
...  
Keyword(s):  
Polymer Synthesis ◽  
Star Polymer ◽  
Polymer Formation ◽  
Star Shaped Polymer

λ-Orthogonal photo-induced ligation in two directions is introduced via a modular, light driven selective star shaped polymer formation.

Applicability of different powder and polymer recipes in a new design powder injection molding system

2021 ◽  
Vol 41 (4) ◽  
pp. 299-309
Author(s):  
Bunyamin Cicek ◽  
Yavuz Sun ◽  
Yunus Turen ◽  
Hayrettin Ahlatci
Keyword(s):  
Injection Molding ◽  
Ethylene Vinyl Acetate ◽  
Powder Injection Molding ◽  
Polymer Composition ◽  
Powder Injection ◽  
New Production ◽  
Spherical Powder ◽  
Polymer Binders ◽  
Polymer Properties ◽  
Microstructure Examination

Abstract Production methods are changing day by day with the developing technology. Based on this idea, a new production logic and machine have been developed owing to polymer-supported powder injection molding (PIM). The ability of this newly designed machine (newPIM) to mold metal or ceramic powders supported by polymer binders is discussed in this study. By taking advantage of the polymer properties such as fluidity and sticking, powders are molded with a specially developed machine with high gas pressure in certain sizes. In this study, in which many parameters are processed from feedstock (FS) production to molding; metals Mg/316L and ceramics SiC/SiO2 powders have been used in different powder sizes and structures. In the newPIM process, polymers were included in four different recipes. Paraffin wax (PW), polyethylene glycol (PEG), polypropylene (PP), ethylene-vinyl acetate (EVA), poly-methyl methacrylate (PMMA) and low-density polyethylene (LDPE) have been employed in the FS with different combinations. From FS production to the molding stage; pressure, microstructure examination, weight loss, and density change features were investigated. The result indicated that the best FS and molding was obtained by the PEG+PMMA polymer composition formed with a spherical powder with a diameter below 40 µm. The compression force of the FS in this composition was observed at approximately 3.4k N values.

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