Structural Analysis of Polyethylene Fibers by Solid State High Resolution NMR; the Distribution of 13C Spin-Lattice Relaxation Times

Kaji, Atsushi; Yamanaka, Akihiro; Murano, Masao

doi:10.1295/polymj.22.893

Cited by 14 publications

(18 citation statements)

References 26 publications

(3 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the contrary, the 34ppm peak due to MCC increases as in higher modulus DF. This result agrees with the NMR studies by A. Kaji et al 26,27 The increase of MCC phase is reported to be caused by drawing. 26,27,29 The structure of MCC is similar to that of ORC in polyethylene.…”

Section: Crystallinity Of Dfssupporting

confidence: 92%

“…This result agrees with the NMR studies by A. Kaji et al 26,27 The increase of MCC phase is reported to be caused by drawing. 26,27,29 The structure of MCC is similar to that of ORC in polyethylene. 29 The analysis of crystal regions and amorphous is possible by peak separation to the two components: crystal (ORC (33ppm), MCC (34ppm)) and amorphous (NC, 31ppm).…”

Section: Crystallinity Of Dfssupporting

confidence: 92%

“…The shoulder at 34ppm is due to monoclinic crystal (MCC). [23][24][25][26][27] Comparing DF(A) with DF(B-D), the 31ppm broad shoulder is small as in higher modulus DF. It suggests that crystallinity increases and amorphous decreases as in higher modulus DF.…”

Section: Crystallinity Of Dfsmentioning

confidence: 97%

“…It is a sharp peak due to orthorhombic crystal (ORC). [23][24][25][26][27] The broad shoulder is observed at the higher field side of the ORC signal. The shoulder peak at 31ppm is due to amorphous region (noncrystal: NC).…”

Section: Crystallinity Of Dfsmentioning

confidence: 99%

“…It is known that crystal and amorphous have different chemical shifts in solid state 13 C-NMR spectra of polyethylene. [23][24][25][26][27] And it is also known about polyethylene that relaxation times of solid state NMR are different between crystal and amorphous because of difference of molecular motions. 26 -28 So, a lot of studies by solid state NMR were reported using peak separation by difference of chemical shifts [23][24][25][26][27] or analysis of relaxation times by difference of molecular motions 26 -28 to investigate phase structure of polyethylene.…”

Section: Thermal Expansion Coefficientmentioning

confidence: 99%

See 4 more Smart Citations

Thermal strain of high strength polyethylene fiber in low temperature

Yamanaka

Kitagawa

Tsutsumi

et al. 2004

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

ABSTRACT:High strength polyethylene fiber (Toyobo, Dyneema® fiber: hereinafter abbreviated to DF) has a negative thermal expansion coefficient. Relation between fiber structure and thermal strain of DF used as reinforcement of DF reinforced plastic (DFRP) for cryogenic use was investigated. The crystallinities and orientation angles of several kinds of polyethylene fibers having different modulus from 15 to 134Gpa (herein after abbreviated to DFs) were measured by NMR and X-ray. We obtained the parameters of the mechanical series-parallel model composed of crystal and amorphous by crystallinity and modulus. Thermal expansion coefficients of DFs were estimated by mechanical seriesparallel model. All DFs having different modulus showed negative thermal expansion coefficients in the temperature range from 180 to 300K, and absolute values of those markedly increased by increasing tensile modulus of DF. The estimated thermal expansion coefficients showed negative values, and thermal strains showed a similar curve to observed ones mostly. Average thermal expansion coefficients in the temperature range from 180 to 300K estimated by mechanical model agreed with the observed ones.

show abstract

Section: Crystallinity Of Dfssupporting

confidence: 92%

Section: Crystallinity Of Dfssupporting

confidence: 92%

Section: Crystallinity Of Dfsmentioning

confidence: 97%

Section: Crystallinity Of Dfsmentioning

confidence: 99%

Section: Thermal Expansion Coefficientmentioning

confidence: 99%

See 3 more Smart Citations

Thermal strain of high strength polyethylene fiber in low temperature

Yamanaka

Kitagawa

Tsutsumi

et al. 2004

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

show abstract

The radiation effect on thermal conductivity of high strength ultra‐high‐molecular‐weight polyethylene fiber by γ‐rays

Yamanaka

Izumi

Kitagawa

et al. 2006

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

ABSTRACT:To understand the contribution to thermal conductivity by the length of the molecular chains in high strength ultra-high-molecular-weight polyethylene (UHMW-PE) fiber, the thermal conductivity in the range of low temperature was investigated for high-strength UHMW-PE fiber (Toyobo, Dyneema; hereinafter abbreviated to DF) irradiated by ␥-rays (␥-rays treatment) that induce the molecular chains scission. The molecular weight of DF decreased by ␥-rays treatment. X-ray diffraction behavior did not change by ␥-rays treatment. The melting behavior observed by differential scanning calorimetry showed the main chain scission of DF by ␥-rays treatment. Heat capacity decreased slightly by ␥-rays treatment. Thermal conductivities of DF with and without ␥-rays treatment decreased by decreasing temperature. Thermal conductivity of DF decreased very much by ␥-rays treatment. The decrease of thermal conductivity was explained by molecular chain scission in DF by ␥-rays treatment and it suggested the possibility of the reduction of mean free path of phonon. The decreasing rates of thermal conductivity by ␥-rays treatment were smaller than those of molecular weight. Those differences were explained by the difference of probability of chain scission between the amorphous and crystal region. Those results suggested the contribution of the length of extended molecular chains because of high molecular weight on the thermal conductivity of DF.

show abstract

Annealing behavior of gel‐spun polyethylene fibers at temperatures lower than needed for significant shrinkage

Бузин

Lin

et al. 2003

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

The annealing at 373 K of ultrastrong, gel-spun polyethylene (PE) has been studied. At this temperature, the fibers show no significant shrinkage. Still, a significant decrease in the mechanical properties is observed. The fibers have been analyzed with differential scanning calorimetry (DSC), temperature-modulated differential scanning calorimetry (TMDSC), atomic force microscopy (AFM), and small-angle X-ray scattering (SAXS). During the annealing, the glass transition of the intermediate phase is exceeded, as shown by DSC. When split for structure analysis by AFM, the annealed fibers undergo plastic deformation around the base fibrils instead of brittle fracture. The quasi-isothermal TMDSC experiments are compared to the minor structural changes seen with SAXS and AFM. The loss of performance of the PE fibers at 373 K is suggested to be caused by the oriented intermediate phase, and not by major changes in the structure or morphology. The overall metastable, semicrystalline structure is shown by TMDSC to posses local regions that can melt reversibly.

show abstract

Structural Analysis of Polyethylene Fibers by Solid State High Resolution NMR; the Distribution of 13C Spin-Lattice Relaxation Times

Cited by 14 publications

References 26 publications

Thermal strain of high strength polyethylene fiber in low temperature

Thermal strain of high strength polyethylene fiber in low temperature

The radiation effect on thermal conductivity of high strength ultra‐high‐molecular‐weight polyethylene fiber by γ‐rays

Annealing behavior of gel‐spun polyethylene fibers at temperatures lower than needed for significant shrinkage

Contact Info

Product

Resources

About