Thermal shrinkage of drawn polystyrene

Ito, Eiko; Horie, Takashi; Kobayashi, Yasuji

doi:10.1002/app.1978.070221114

Cited by 18 publications

(6 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An example from the literature is presented in Figure 7 . According to [ 17 ], pressed polystyrene sheets were stretched at 130 °C and a rate of 4%/min up to different draw ratios

, and then precipitated. Subsequently, the stretched sheets were heated for 15 min at different temperatures below and above the glass temperature of 90 °C, and their lengths

after recovery measured, from which the shrinkage ratio

was determined.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Recoverable Extensional Flow of Polymer Melts and Its Relevance for Processing

Münstedt

2020

Polymers

View full text Add to dashboard Cite

While the uniaxial elongational viscosity is widely investigated, and its relevance for processing is described in the literature, much less has been published on the recoverable extensional flow of polymer melts. This paper presents a short overview of the dependencies of the recoverable elongation on the molecular structure of a polymer, and on some experimental parameters. Its main focus lies on the discussion of processing operations and applications that are largely affected by the elastic components of elongational flow. The recoverable portions of stretched films are considered, and the exploitation of the shrinkage of films, due to the recovery of frozen recoverable deformations, and its role for applications are addressed. The analysis of measurements of velocity fields in the entry region of a slit die and results on the determination of the recoverable elongation from uniaxial experiments, according to the literature, lead to the conclusion of dominant elastic extensions. Considering these facts, the assumptions for Cogswell’s widely used method of determining elongational viscosities under processing conditions from entrance flow are not realistic. As examples of a direct application of extrudate swell from short dies for processing, pelletizing and fused deposition modelling within additive manufacturing are addressed. The special features of extrudate swell from short dies, and uniaxial recoverable elongation for a polymer filled with rigid particles in comparison to an immiscible polymer blend, are presented and discussed.

show abstract

“…An example from the literature is presented in Figure 7 . According to [ 17 ], pressed polystyrene sheets were stretched at 130 °C and a rate of 4%/min up to different draw ratios

, and then precipitated. Subsequently, the stretched sheets were heated for 15 min at different temperatures below and above the glass temperature of 90 °C, and their lengths

after recovery measured, from which the shrinkage ratio

was determined.…”

Section: Resultsmentioning

confidence: 99%

“… Shrinkage ratio

as function of the annealing temperature

of polystyrene films previously stretched to different draw ratios

at 130 °C and subsequently precipitated. The annealing time was 15 min [ 17 ]. …”

Section: Figurementioning

confidence: 99%

Recoverable Extensional Flow of Polymer Melts and Its Relevance for Processing

Münstedt

2020

Polymers

View full text Add to dashboard Cite

show abstract

“…[44][45][46][47][48] The weak surface adhesion of PDMS, on the other hand, can act as "internal lubrication" in the spinning process, promoting the unentanglement of PLA molecules to generate a more oriented structure. 49,50 Moreover, the interfacial interaction between the nano-SiO 2 particles and the PLA matrix contributed to the tenacity of the fibers. According to the thermal shrinkage data of these fibers, the shrinkage of the PLA fibers increased with increasing silicone powder content (Table 2), indicating that the orientation of the amorphous molecular chains within the fibers increased, further supporting the above inference.…”

Section: Mechanical Properties Of Hydrophobic Pla Fibersmentioning

confidence: 99%

Facile fabrication of stain‐resistant poly(lactic acid)/silicone powder fibers: Comprehensive structure characterization and performance evaluation

Sun,

Zheng,

Guan

et al. 2024

J of Applied Polymer Sci

View full text Add to dashboard Cite

Due to their eco‐friendly and functional attributes, the development of stain‐resistant poly(lactic acid) (PLA) fibers offers a multitude of benefits, including enhanced sustainability, ease of maintenance and expanded application fields. To investigate the feasibility of facile fabrication of stain‐resistant poly(lactic acid) (PLA) fibers, hydrophobic PLA fibers were produced using a scalable melt spinning technique employing silicone powder as the hydrophobic functional material. The influence of silicone powder content on the morphology and crystal structure of PLA fibers was investigated using different length scale characterization methods, including scanning electron microscopy and wide‐angle X‐ray diffraction. The relationships between the mechanical performance, hydrophobicity, and structure of the PLA fibers were established. The results showed that the synergistic effect of the micro/nanoconvex structure on the fiber surface created by silicon dioxide (SiO2) in silicone powder and the low surface energy of polydimethylsiloxane (PDMS) can considerably improve the hydrophobic functionality of the fibers. Compared with that of PLA fibers, the contact angle of hydrophobic PLA fibers increases from 67.3° to 87.6° with the addition of 3 wt% silicone powder. Furthermore, although silicone powder may accelerate PLA crystallization nucleation, it does not increase the crystallite size. When the silicone powder content is increased to 4 wt%, the mesophase fraction of the hydrophobic PLA fibers increases from 9.3% to 13.7%. This is the primary structural factor that allows the fiber to maintain its good tenacity. The tenacity of these hydrophobic PLA fibers is approximately 4.5 cN/dtex, which has excellent practical value.

show abstract

“…Although not so often, here and there in the literature we have seen statement directly or indirectly mentioning that all polymeric materials should have the SME (most likely meant for the thermo-responsive SME, e.g., in a very recent publication by Mendez et al [30]). Some early experiments conducted on some commonly used engineering polymers (e.g., in [31][32][33][34][35][36][37][38][39][40][41][42][43][44]) have indicated the shape recovery phenomenon after annealing.…”

mentioning

confidence: 99%

Shape memory technology : working mechanisms, modeling and surface patterning application

Zhao¹

View full text Add to dashboard Cite

A new way to classify shape memory materials (SMMs) was proposed based on the underlying working mechanisms behind the shape memory effect (SME). Three categories, namely dual-state mechanism, dual-component mechanism, and partial-transition mechanism, were discussed in details. Based on this, the concept of advanced shape memory technology was proposed to enable the SME in materials, to design/synthesize new SMMs with tailored features, and to optimize the SME in materials. Previously, SME is considered as a unique behavior in some certain materials. In this study, based on ASMT, SME can be achieved in a range of materials, which are not the traditional SMMs. A generic 3-D model was developed to simulate the shape memory behavior in polymeric SMMs. This model was verified by a series of experiments. In addition, this model was applied for optimization of the SME. The thermo-/chemo-responsive SME in poly(methyl methacrylate) (PMMA) were systematically studied by experiments and simulation. Based on above study on the fundamentals, different surface patterning methods were developed to fabricate micro/nano-sized surface features, including well-controllable wrinkled patterns, PMMA microlens arrays, reversible surface patterns and 3-D surface patterns.

show abstract

Thermal shrinkage of drawn polystyrene

Cited by 18 publications

References 16 publications

Recoverable Extensional Flow of Polymer Melts and Its Relevance for Processing

Recoverable Extensional Flow of Polymer Melts and Its Relevance for Processing

Facile fabrication of stain‐resistant poly(lactic acid)/silicone powder fibers: Comprehensive structure characterization and performance evaluation

Shape memory technology : working mechanisms, modeling and surface patterning application

Contact Info

Product

Resources

About