scholarly journals Poly(butylene succinate-co-butylene acetylenedicarboxylate): Copolyester with Novel Nucleation Behavior

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 365
Author(s):  
Yi Li ◽  
Guoyong Huang ◽  
Cong Chen ◽  
Xue-Wei Wei ◽  
Xi Dong ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
Specific Interaction ◽  
Crystallization Rate ◽  
Amorphous Region ◽  
Nucleation Mechanism ◽  
Crystal Modification ◽  
Butylene Succinate ◽  
Nucleation Behavior ◽  
Primary Nucleation ◽  
New Type

Big spherulite structure and high crystallinity are the two main drawbacks of poly(butylene succinate) (PBS) and hinder its application. In this work, a new type of copolyester poly(butylene succinate-co-butylene acetylenedicarboxylate) (PBSAD) is synthesized. With the incorporation of acetylenedicarboxylate (AD) units into PBS chains, the crystallization temperature and crystallinity are depressed by excluding AD units to the amorphous region. In contrast, the primary nucleation capability is significantly strengthened, without changing the crystal modification or crystallization kinetics, leading to the recovery of total crystallization rate of PBSAD under the same supercooling condition. The existence of specific interaction among AD units is found to be crucial. Although it is too weak to contribute to the melt memory effect at elevated temperature, the interaction continuously strengthens as the temperature falls down, and the heterogeneous aggregation of AD units keeps growing. When the aggregating process reaches a certain extent, it will induce the formation of a significant amount of crystal nuclei. The unveiled nucleation mechanism helps to design PBS copolymer with good performance.

scholarly journals Dependence of Crystallization Behavior of Interacting Telechelic Poly(butylene succinate) Oligomer on Molecular Weight

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1530
Author(s):  
Cong Chen ◽  
Xue-Wen Zhang ◽  
Hai-Mu Ye
Keyword(s):  
Growth Rate ◽  
Crystallization Rate ◽  
Crystal Nucleation ◽  
Nucleation Density ◽  
Butylene Succinate ◽  
Nucleation Behavior ◽  
Crystalline Polymers ◽  
Molecular Weights ◽  
Primary Nucleation ◽  
The Impact

A large spherulite structure deteriorates the mechanical properties of crystalline polymers, and therefore various methods have been explored to increase primary nucleation density. Recently, chain-end modification has been proposed as an effective approach for regulating polymer crystal nucleation. However, the relevant nucleation mechanism still requires investigation. Therefore, in this work, 2-ureido-4[1H]-pyrimidinone (UPy) units, which can form stacks via quadruple hydrogen bonds with each other, are introduced as end groups for the preparation of interacting telechelic poly(butylene succinate) (PBS-UPy) oligomers with different molecular weights (Mns). The crystallization, especially the nucleation behavior of PBS-UPy, is studied in detail by comparing with the corresponding pre-polymer, the hydroxyl-terminal PBS (PBS-OH). The thermal properties of PBS-UPy exhibit similar Mn-dependent tendency to those of PBS-OH, but with weaker total crystallization rate. The spherulite growth rate is significantly reduced, whereas the primary nucleation density is highly promoted, after introducing UPy groups. Further investigation reveals that the mechanism of UPy stacks’ influence on nucleation ability changes from inhibition to promotion with respect to Mn. Even under an inhibition of nucleation ability, the final nucleation density is obviously increased because of a significant decline of the growth rate. In addition, the change in the impact of UPy stacks on nucleation ability is speculated to originate from the memory expression feasibility of ordered conformation in the melt during crystallization.

Carbohydrate-Carbohydrate Recognition Promotes Cell Adhesion

2005 ◽  
Vol 872 ◽  
Author(s):  
Christine Gourier ◽  
Eric Perez ◽  
Yongmin Zhang ◽  
Pierre Sinaÿ
Keyword(s):  
Cell Adhesion ◽  
Specific Interaction ◽  
High Sensitivity ◽  
Second Step ◽  
Specific Interactions ◽  
Carbohydrate Recognition ◽  
Giant Vesicles ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
New Type

AbstractRecently, carbohydate-carbohydrate recognition has emerged as a new type of interaction in cell adhesion processes. One of these carbohydrates, the LewisX determinant (LeX), has been shown to be involved in murine embryogenesis. Here we confirm the existence of this specific interaction by measuring the adhesion between giant vesicles functionalised with synthetic Lex bearing lipids providing to the LeXdeterminent a high orientational freedom. This was obtained by micropipette aspiration and contact angle measurements. By using a simple model involving the several contributions to the adhesion free energy, specific and non specific interactions could be separated and quantified. In a second step, using natural Lex bearing sphingolipids, we could underscore the high sensitivity of LeX-LeX recognition to molecular structure and prove that the possible orientations provided by the natural LeX bearing molecules not only allow but strongly favor LeX-LeX recognition.

scholarly journals Enzymatic Degradation of Acrylic Acid-Grafted Poly(butylene succinate-co-terephthalate) Nanocomposites Fabricated Using Heat Pressing and Freeze-Drying Techniques

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 376 ◽  
Author(s):  
Sheng-Hsiang Lin ◽  
Hsiang-Ting Wang ◽  
Jie-Mao Wang ◽  
Tzong-Ming Wu
Keyword(s):  
Acrylic Acid ◽  
Freeze Drying ◽  
Crystallization Rate ◽  
X Ray Diffraction ◽  
Butylene Succinate ◽  
Covalent Bonds ◽  
Polymer Backbone ◽  
Transmission Electron ◽  
Degradation Rates ◽  
Organically Modified

Biodegradable acrylic acid-grafted poly(butylene succinate-co-terephthalate) (g-PBST)/organically modified layered zinc phenylphosphonate (m-PPZn) nanocomposites were effectively fabricated containing covalent bonds between the g-PBST and m-PPZn. The results of wide-angle X-ray diffraction and transmission electron microscopy revealed that the morphology of the g-PBST/m-PPZn nanocomposites contained a mixture of partially exfoliated or intercalated conformations. The isothermal crystallization behavior of the nanocomposites showed that the half-time for crystallization of 5 wt % g-PBST/m-PPZn nanocomposites was less than 1 wt % g-PBST/m-PPZn nanocomposites. This finding reveals that increasing the loading of m-PPZn can increase the crystallization rate of nanocomposites. Degradation tests of g-PBST/m-PPZn nanocomposites fabricated using the heat pressing and the freeze-drying process were performed by lipase from Pseudomonas sp. The degradation rates of g-PBST-50/m-PPZn nanocomposites were significantly lower than those of g-PBST-70/m-PPZn nanocomposites. The g-PBST-50 degraded more slowly due to the higher quantity of aromatic group and increased stiffness of the polymer backbone. The degradation rate of the freeze-drying specimens contained a more extremely porous conformation compared to those fabricated using the heat pressing process.

Base-Catalyzed Hydrolysis Behavior of PLA/PBS Blends

2013 ◽  
Vol 821-822 ◽  
pp. 941-944
Author(s):  
Shi Jie Zhang ◽  
Yi Wen Tang ◽  
Li Hua Cheng
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Degradation Rate ◽  
Degradation Process ◽  
Poly Lactic Acid ◽  
Biodegradable Materials ◽  
Butylene Succinate ◽  
New Type

Poly (butylene succinate) (PBS) was mixed with Poly (lactic acid) (PLA) through Haake Reomix, a new type of biodegradable materials can be obtained. With the increasing addition of PBS and the raise of the solution basicity, the degradation rate of blends increase sharply. The GPC analysis can approve the reduction of molecular weight in the degradation process of PLA/PBS blends.

Effects of Attapulgite on the Isothermal Crystallization Behavior of Poly(Butylene Succinate-co-Butylene Adipate)

2013 ◽  
Vol 791-793 ◽  
pp. 56-59
Author(s):  
Zhi Guo Qi ◽  
Jin Nan Chen ◽  
Bao Hua Guo ◽  
Yu Zhang
Keyword(s):  
Crystallization Kinetics ◽  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Crystallization Behavior ◽  
Growth Form ◽  
Crystallization Rate ◽  
Melt Mixing ◽  
Butylene Succinate ◽  
Isothermal Crystallization Kinetics ◽  
Kinetics Of

Poly (butylene succinate-co-butylene adipate)/attapulgite nanocomposites were prepared by melt mixing in a HAAKE mixer. The crystallization kinetics of PBSA and its nanocomposites was studied under isothermal conditions by differential scanning calorimetr. The isothermal crystallization kinetics results indicated that attapulgite can induce heterogeneous nucleation, resulting in an improvement on the crystallization temperature and crystallization rate. Both the PBSA and its nanocomposites were correlated to the spherulitic growth form.

Al–Fe-based bulk quasicrystalline alloys with high elevated temperature strength

2000 ◽  
Vol 15 (12) ◽  
pp. 2737-2744 ◽  
Author(s):  
Hisamichi M. Kimura ◽  
Kenichiro Sasamori ◽  
Akihisa Inoue
Keyword(s):  
Elevated Temperature ◽  
Size Fraction ◽  
The United States ◽  
Decomposition Temperature ◽  
Mixed Structure ◽  
Elevated Temperature Strength ◽  
Average Grain Size ◽  
New Type ◽  
Strength Material ◽  
Ti Powder

An icosahedral (I) phase in coexistence with Al phase was found to precipitate in atomized Al93Fe3Cr2Ti2 and Al93Fe3Cr2V2 powders. The mixed structure was formed in the size fraction range up to 125 μm for the Al–Fe–Cr–V alloy, while the increase of the particle size to 125 μm for the Al–Fe–Cr–Ti powder led to the precipitation of Al23Ti9. The replacement of Cr by Mn for the Al93Fe3Cr2Ti2 powder caused a mixed structure of Al+I+Al23Ti9 +Al6Mn even for the ?26 mm powder. The formation tendency of the I-phase increased in the order of Al–Fe–Cr–V > Al–Fe–Cr–Ti > Al–Fe–Mn–Ti system. The decomposition temperature of the I-phase was about 790 K. The I particles were analyzed to have approximate compositions of Al84.2Fe7.0Cr6.3Ti2.5 and Al82.9Fe9.0Mn6.4Ti1.7, and the use of the analytical compositions enabled the formation of a mostly single I phase with an average grain size of 90 to 130 nm in the melt-spun state. Bulk I alloys in a cylindrical rod form were produced by extrusion of the atomized powders at 673 K and an extrusion ratio of 10. The extruded Al93Fe3Cr2Ti2 alloys exhibited good mechanical properties; i.e., σ 0.2 of 550 MPa, σ UTS of 660 MPa, and ε P of 4.5% at room temperature, and σ 0.2 of 330 MPa, σ UTS of 350 MPa, and ε P of 1.5% at 573 K. The high σ UTS exceeding 350 MPa at 573 K was superior to the final target of the United States Air Force and hence the I-based Al93Fe3Cr2Fe2 alloy is expected to be extended as a new type of high elevated temperature strength material.

scholarly journals Numerical Frameworks for Laser-Induced Cavitation: Is Interface Supersaturation a Plausible Primary Nucleation Mechanism?

2020 ◽  
Vol 20 (11) ◽  
pp. 7276-7290
Author(s):  
Niklas Hidman ◽  
Gaetano Sardina ◽  
Dario Maggiolo ◽  
Henrik Ström ◽  
Srdjan Sasic
Keyword(s):  
Nucleation Mechanism ◽  
Primary Nucleation

Crystallization behavior of poly(p-dioxanone) with cyclodextrin complex and nucleation mechanism discussion

RSC Advances ◽  
2016 ◽  
Vol 6 (90) ◽  
pp. 87169-87178 ◽  
Author(s):  
Xiao-bo Xu ◽  
Qing Li ◽  
Cheng-dong Xiong
Keyword(s):  
Inclusion Complex ◽  
Crystallization Behavior ◽  
Crystallization Rate ◽  
Nucleating Agent ◽  
Nucleation Mechanism ◽  
Solution Technique ◽  
Cyclodextrin Complex

In the interest of improving the crystallization rate of poly(p-dioxanone) (PPDO), an inclusion complex (IC) based on β-cyclodextrin (β-CD) and polyglycolide (PGA) serving as a green nucleating agent for PPDO was achieved by a solution technique.

Influence of elevated temperature on alkali-activated ground granulated blast furnace slag concrete

2019 ◽  
Vol 11 (2) ◽  
pp. 247-260
Author(s):  
Virendra Kumar ◽  
Amit Kumar ◽  
Brajkishor Prasad
Keyword(s):  
Blast Furnace ◽  
Elevated Temperature ◽  
Blast Furnace Slag ◽  
Elevated Temperatures ◽  
Experimental Result ◽  
Content Type ◽  
Granulated Blast Furnace Slag ◽  
New Type ◽  
Furnace Slag ◽  
Alkali Activated

Purpose This paper aims to present an experimental investigation on the performances of alkali-activated slag (AAS) concrete and Portland slag cement (PSC) concrete under the influence of elevated temperature. In the present study, the alkali-activated binder contains 85% of ground granulated blast furnace slag (GGBFS) and 15% of powder blended as chemical activators. Design/methodology/approach For the purpose, standard size of cube, cylinder and prism have been cast for a designed mix of concrete. The AAS concrete specimens were kept for water as well as air curing. After attaining the maturity of 28 days, the samples were first exposed to different elevated temperatures, i.e. 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C and 800°C. Later on, the tests were conducted on these samples to find the change in weight and the residual strength of the concrete. Findings After 500°C exposure, a considerable amount of the strength loss has been observed for AAS concrete. It has been evaluated that the performance of AAS concrete is better than that of the PSC concrete at elevated temperature. Research limitations/implications The present research work is being applied on the material for which the experimental result has been obtained. Practical implications The author has tried to develop a new type of binder by using steel industry waste material and then tested at elevated temperature to sustain at high temperatures. Social implications This research may give a social impact for developing mass housing project with a lower cost than that of using a conventional binder, i.e. cement. Originality/value A new type of binder material is being developed.

scholarly journals Hot Deformation Behavior and Microstructure Evolution of Fe–5Mn–3Al–0.1C High-Strength Lightweight Steel for Automobiles

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2478
Author(s):  
Guangming Liu ◽  
Jinbin Wang ◽  
Yafeng Ji ◽  
Runyuan Hao ◽  
Huaying Li ◽  
...  
Keyword(s):  
Dynamic Recrystallization ◽  
Microstructure Evolution ◽  
Hot Deformation ◽  
Deformation Behavior ◽  
Flow Behavior ◽  
Nucleation Mechanism ◽  
Hot Deformation Behavior ◽  
Deformation Parameters ◽  
Primary Nucleation ◽  
Δ Ferrite

The hot deformation behavior of a newly designed Fe–5Mn–3Al–0.1C (wt.%) medium manganese steel was investigated using hot compression tests in the temperature range of 900 to 1150 °C, at constant strain rates of 0.1, 1, 2.5, 5, 10, and 20 s−1. A detailed analysis of the hot deformation parameters, focusing on the flow behavior, hot processing map, dynamic recrystallization (DRX) critical stress, and nucleation mechanism, was undertaken to understand the hot rolling process of the newly designed steel. The flow behavior is sensitive to deformation parameters, and the Zener–Hollomon parameter was coupled with the temperature and strain rate. Three-dimensional processing maps were developed considering the effect of strain and were used to determine safe and unsafe deformation conditions in association with the microstructural evolution. In the deformation condition, the microstructure of the steel consisted of δ-ferrite and austenite; in addition, there was a formation of DRX grains within the δ-ferrite grains and austenite grains during the hot compression test. The microstructure evolution and two types of DRX nucleation mechanisms were identified; it was observed that discontinuous dynamic recrystallization (DDRX) is the primary nucleation mechanism of austenite, while continuous dynamic recrystallization (CDRX) is the primary nucleation mechanism of δ-ferrite. The steel possesses unfavorable toughness at the deformation temperature of 900 °C, which is mainly due to the presence of coarse κ-carbides along grain boundaries, as well as the lower strengthening effect of grain boundaries. This study identified a relatively ideal hot processing region for the steel. Further exploration of hot roll tests will follow in the future.

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