Epitaxial Crystallization of Isotactic Poly(methyl methacrylate) from Different States on Highly Oriented Polyethylene Thin Film

Guo, Zhenjiang; Li, Shuya; Liu, Xueying; Zhang, Jie; Li, Huihui; Sun, Xiaoli; Ren, Zhongjie; Yan, Shouke

doi:10.1021/acs.jpcb.8b08193

Cited by 20 publications

(16 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consequently, the orientation of the crystal could not propagate by epitaxial growth. For lamellar polymer crystals, only the ( hk 0) planes can assure oriented crystal growth. − Nonetheless, in our study, we observed large stacks of flat-on crystals uniquely oriented in the plane. Accordingly, the mechanism of this crystallization process leading to stacking must differ from epitaxial crystallization.…”

Section: Resultsmentioning

confidence: 48%

Formation of Stacked Three-Dimensional Polymer “Single Crystals”

2021

Self Cite

View full text Add to dashboard Cite

Stacks of crystalline lamellae all having a uniquely oriented hexagonal shape, referred to as “3D (three-dimensional) single crystals”, were obtained via isothermal crystallization of isotactic polystyrene at a temperature close to the melting point. The height of the stacks of lamellae reached several micrometers corresponding to hundreds of superposed lamellar crystals. We propose that the mechanism of self-induced nucleation allowed propagating the orientation of the basal lamellar crystal to all other lamellae in the stack. The unique orientation of all lamellae was reflected by the preference of cracks to form along the diagonals of the hexagonal stack. Cracks were caused by a mismatch in the coefficients of thermal expansion of the substrate and “3D single crystals” during quenching from the crystallization temperature to room temperature. We believe that the presented growth mechanisms leading to “3D single crystals” can be observed for all crystallizable polymers including block copolymers with a noncrystallizable block.

show abstract

Section: Resultsmentioning

confidence: 48%

Formation of Stacked Three-Dimensional Polymer “Single Crystals”

2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…As already presented in the introduction part as Figure a, the melt‐drawn iPBu thin films exhibit a fibrillar structure of its form I crystals. However, the morphology of the melt‐drawn PE thin films is totally different from that of iPBu . Figure shows the phase contrast BF electron micrograph and its corresponding ED pattern of a melt‐drawn PE ultrathin film.…”

Section: Techniques For Preparing Highly Oriented Polymer Thin Filmsmentioning

confidence: 98%

Section: Techniques For Preparing Highly Oriented Polymer Thin Filmsmentioning

confidence: 99%

Preparation and Self‐Repairing of Highly Oriented Structures of Ultrathin Polymer Films

Xin

Hou

et al. 2019

Macro Chemistry & Physics

Self Cite

View full text Add to dashboard Cite

Thin and ultrathin polymer films play an important role in a variety of applications, such as electronics, liquid crystal alignment, adhesion, and so on. It is well established that the properties of semicrystalline polymeric materials depend remarkably on their multiscale structures; for example, an increase of more than a factor of 100 has been reported for the electrical conductivity of doped and aligned conjugated macromolecules compared with their nonoriented counterparts. Consequently, sophisticated methods have been developed for preparing highly oriented polymer ultrathin films. It should be pointed out that the highly oriented crystalline structure of polymers can be maintained only at temperatures below their melting points. Otherwise, structure rearrangement will result in the loss of orientation and therefore the properties. Therefore, self‐repairing of highly oriented polymer structures is of great significance for the long‐term application of polymer thin films in some specific fields. In this review paper, the preparation and self‐repair of the highly oriented structure of polymer thin films is described in the hopes that this will afford useful information for further development of polymeric materials for advanced applications.

show abstract

“…On the other hand, the crystallization of poly[(R)-3-hydroxybutyrate] (PHB) in its miscible blends with PVDF under strain causes an a-axis orientation of PHB along the stretching direction [21]. For the crystalline/crystalline polymer blends, the crystal structure and orientation of later crystallized components can be controlled by epitaxy or transcrystallization at the surface of early formed crystals [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37], which may not reflect the effect of strain and the blending component on the later crystallized component correctly. It should be pointed out that soft epitaxy can hardly take place in crystalline/amorphous polymer blends, since it is not a common phenomenon [38,39].…”

Section: Introductionmentioning

confidence: 99%

Orientation of Poly(ε-caprolactone) in Its Poly(vinyl chloride) Blends Crystallized under Strain: The Role of Strain Rate

et al. 2020

Self Cite

View full text Add to dashboard Cite

The blends of high and low molecular weights poly(ε-caprolactone) (PCL) with poly(vinyl chloride (PVC) were prepared. The samples before and after the crystallization of PCL were uniaxially stretched to different draw ratios. The orientation features of PCL in a stretched crystalline PCL/PVC blend and crystallized from the amorphous PCL/PVC blends under varied strains were studied by wide-angle X-ray diffraction (WAXD). It was found that a uniaxial stretching of crystalline PCL/PVC blend with high molecular weight PCL results in the c-axis orientation along the stretching direction, as is usually done for the PCL bulk sample. For the stretched amorphous PCL/PVC blend samples, the crystallization of high molecular weight PCL in the blends under a draw ratio of λ = 3 with a strain rate of 6 mm/min leads to a ring-fiber orientation. In the samples with draw ratios of λ = 4 and 5, the uniaxial orientation of a-, b-, and c-axes along the strain direction coexist after crystallization of high molecular weight PCL. With a draw ratio of λ = 6, mainly the b-axis orientation of high molecular weight PCL is identified. For the low molecular weight PCL, on the contrary, the ring-fiber and a-axis orientations coexist under a draw ratio of λ = 3. The a-axis orientation decreases with the increase of draw ratio. When the λ reaches 5, only a poorly oriented ring-fiber pattern has been recognized. These results are different from the similar samples stretched at a higher strain rate as reported in the literatures and demonstrate the important role of strain rate on the crystallization behavior of PCL in its blend with PVC under strain.

show abstract

Epitaxial Crystallization of Isotactic Poly(methyl methacrylate) from Different States on Highly Oriented Polyethylene Thin Film

Cited by 20 publications

References 62 publications

Formation of Stacked Three-Dimensional Polymer “Single Crystals”

Formation of Stacked Three-Dimensional Polymer “Single Crystals”

Preparation and Self‐Repairing of Highly Oriented Structures of Ultrathin Polymer Films

Orientation of Poly(ε-caprolactone) in Its Poly(vinyl chloride) Blends Crystallized under Strain: The Role of Strain Rate

Contact Info

Product

Resources

About