Dynamic rheology and relaxation time spectra of oil-based self-degradable gels

Abstract

In oil well treatments, such as matrix stimulations or water shut‐off, it is often necessary to temporary isolate or protect productive zones with chemical diverting agents. In this work, a solution of peroxide crosslinked styrene‐butadiene rubber (SBR) has been transformed to a self‐degradable gel system by adding hydroperoxide as a degradation agent to the formulation. This oil‐based self‐degradable gel has been characterized by linear oscillatory rheometry. In situ and ex situ experiments were performed to evaluate the evolution of crosslinking and degradation reactions, including the liquid‐solid transition. Relaxation time spectra were calculated from dynamic mechanical frequency sweeps. Structural changes in the polymer network were visible within the relaxation time spectra, since it qualitatively showed the contribution of local simple entanglements and chemical covalent bonds to the final rheological behavior. The influence of peroxide concentration, polymer concentration, hydroperoxide concentration, and temperature have been studied and described in terms of rheological changes. Finally, a hydrogen donor aromatic solvent was used as scavenger to retard both crosslinking and degradation reactions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 433–444

Effect of Hydrogen Bonding on Dynamic Rheological Behavior of PVA Aqueous Solution

“…In addition, the relaxation spectrum is the most general method to describe the dependence of material viscoelasticity on time or frequency. Through the study of the relaxation spectrum, the distribution of relaxation time ( τ ) and the contribution of various motion modes to macroscopic viscoelasticity can be fully grasped, so as to provide an effective way for studying the microstructure of viscoelastic materials [ 7 , 23 , 24 ].…”

Synthesis, characterization and self-assembly of linear and miktoarm star copolymers of exclusively immiscible polydienes

“…33 Apart from their self-assembly capability, polymers consisted of at least one elastomeric unit exhibit interest in the field of rheology, due to their fatigue resistance and viscoelastic properties, rendering them appealing materials as adhesives for industrial applications. [34][35][36][37][38][39][40] In this study, we report the synthesis of four ( 4) linear diblock copolymers of the PB 1,4 -b-PI 3,4 sequence, four (4) asymmetric miktoarm star copolymers of the PB 1,4 (PI 3,4 ) 2 , and four (4) of the PB 1,4 (PI 3,4 ) 3 type. The synthesis procedure and properties of such non-linear copolymers have not been reported in the literature yet.…”