Behavior of polyethylene in a variable temperature density gradient column

Hammonds, Ryan L.; Stephens, C.P.; Wills, Aj; Hallman, Russell; Benson, Robert D.

doi:10.1016/j.polymertesting.2013.07.011

Cited by 5 publications

(3 citation statements)

References 20 publications

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“…Potential reason for the different crystallinities calculated from XRD (Table 2) and DSC (Table 3) results could be the fact that DSC results capture the mass-based degree of crystallinity, whereas the XRD results capture the volume-based degree of crystallinity. [77] As DSC results suggest, this SMPU LCM could be pumped to the wellbore and seal the fractures once activated by the formation temperature to near T m = 59 °C. By changing the HSC or PCL MW the working temperature range of SMPU LCM could be changed to best a wellbore temperature profile.…”

Section: Further Characterization Of the Synthesized Pcl And Smpumentioning

confidence: 94%

Shape Memory Polyurethane as a Drilling Fluid Lost Circulation Material

Lashkari

Tabatabaei‐Nezhad

Husein

2021

Macro Materials & Eng

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Drilling fluid loss is a major problem with serious economic and environmental consequences. The use of traditional lost circulation materials (LCMs) to seal wide fractures increases the risk of bit nozzle plugging. In this work, smart LCMs based on shape memory polyurethane (SMPU) are proposed for the first time. SMPU can be programmed to recover at temperatures suited to a given well. As such, SMPU smoothly passes through the bit nozzles, while effectively seal wide fractures once activated. The SMPU is prepared by two step pre-polymerization and characterized by Fourier transform infrared spectra, X-ray diffraction, and differential scanning calorimeter. The SMPU is programmed by changing and fixing the original shape to a temporary shape through a thermo-mechanical process. The shape memory behavior of SMPU is analyzed by tensile apparatus. Compatibility of SMPU with WBMs is determined from mud rheology and filtration tests. Fracture sealing efficiency and shape recovery of SMPU are evaluated by a modified particle permeability apparatus fitted with a model fracture. The results confirm high sealing and shape recovery attributes of SMPU. The plug formed at 114 kg m -3 SMPU and 80 °C experiences a sealing pressure of 100 bar with 71.5 cm 3 cumulative fluid loss.

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Section: Further Characterization Of the Synthesized Pcl And Smpumentioning

confidence: 94%

Shape Memory Polyurethane as a Drilling Fluid Lost Circulation Material

Lashkari

Tabatabaei‐Nezhad

Husein

2021

Macro Materials & Eng

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“…The knowledge about structure reorganization upon heating/ cooling is critical for processing and creating polymeric materials with pre-defined properties [1][2][3][4]. Despite numerous studies [1][2][3][4][5][6][7][8][9][10] on the temperature behavior of polymers to-date, certain key features about structural changes with temperature remain a subject of critical discussion even for the simplest and well-studied polyethylene (PE) [3]. For instance, the existence of an intermediate phase, which is structurally * Author to whom any correspondence should be addressed.…”

Section: Introductionmentioning

confidence: 99%

“…or conformationally different from both the crystalline and the disordered amorphous phases, and its role in crystallization/melting and mechanical relaxation processes have been the subject of discussion for some decades already [2,3,5,7,[9][10][11][12][13][14]. Three (the high temperature α-relaxation and the low-temperature β-and γ-relaxation) relaxation processes lying below the melting temperature T m , and another thermal transition (termed λ) just above T m , i.e.…”

Section: Introductionmentioning

confidence: 99%

Sensitive temperature-dependent phase resolution of polyethylene-clay nanocomposites

Sagitova¹,

Donfack²,

Prokhorov³

et al. 2022

Laser Phys.

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With the help of spectroscopic and differential scanning calorimetry (DSC) techniques, we have studied conformational and phase reorganizations as function of temperature in intercalated polymer-clay nanocomposites based on low-, middle-, and high-density polyethylene (PE) matrices. We show that Raman spectroscopy is sensitive to structural changes appearing during heating at much lower temperatures (about 47 °C) in comparison to DSC measurements. In fact, in the melting region where DSC traces show endotherms, Raman spectra reveal dramatic changes in the phase and conformational compositions of PE and PE-matrices within PE-clay nanocomposites. Noteworthy, the structural reorganization pathway, through which the semicrystalline nanocomposites transform into a melt state, depends primarily on the PE density and weakly on the filler (nanoclay). Moreover, the temperature-dependent crystallinity degree and the total amount of trans-conformers of the PE system are determined, and the evidence for the formation of intermediate crystal-like phase during heating is shown.

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