A Study of the Crystallization Behaviour of Dynamically Vulcanized EPDM/Nylon Copolymer Blends

2003 ◽  
Vol 11 (6) ◽  
pp. 449-463
Author(s):  
Xin Liu ◽  
Hua Huang ◽  
Yong Zhang ◽  
Yinxi Zhang
Keyword(s):  
Crystallization Process ◽  
Nucleating Agent ◽  
Avrami Equation ◽  
Relative Crystallinity ◽  
Epdm Rubber ◽  
Chlorinated Polyethylene ◽  
Copolymer Blends ◽  
Dispersed Particles ◽  
Kinetics Of ◽  
Diene Rubber

In this work the crystallization kinetics of polyamide copolymer (PA) in PA/ ethylene-propylene-diene rubber (EPDM) thermoplastic vulcanizates was studied under non-isothermal and isothermal conditions from the melt. A differential scanning calorimeter was used to monitor the energetics of the crystallization process. The effects of rubber, compatibilizer, vulcanizing agents, and the process methods on the isothermal and non-isothermal crystallization of PA were investigated. Relative crystallinity develops in accordance with the time dependence described by the Avrami equation with the exponent n ≈ 3. The experimental results show that the EPDM rubber is not the nucleating agent in those samples that were not dynamically vulcanized. The addition of chlorinated polyethylene has no effect on the crystallization of PA. But in dynamically vulcanized samples the EPDM rubber is a nucleating agent and the addition of chlorinated polyethylene helps the EPDM to form fine and well-dispersed particles and improves the crystallization of PA.

The Crystallization Kinetics of Polypropylene/Organo Montmorillonite Nanocomposites Modified with Calcium Pimelate

2013 ◽  
Vol 747 ◽  
pp. 749-752
Author(s):  
Nattha Thanomchaem ◽  
Wunpen Chonkaew
Keyword(s):  
Crystallization Kinetics ◽  
Nucleating Agent ◽  
Crystal Form ◽  
Avrami Equation ◽  
Crystallization Time ◽  
Relative Crystallinity ◽  
Twin Screw ◽  
Higher Temperature ◽  
Kinetics Of ◽  
Montmorillonite Nanocomposites

Polypropylene/organo montmorillonite nanocomposites modified with 0.001-0.1 wt% calcium pimelate, a β-nucleating agent, were prepared using twin screw extruder. The effects of calcium pimelate content on crystallization behavior were investigated using differential scanning calorimeter (DSC). The crystallization kinetics were studied using both nonisothermal and isothermal methods. The development of relative crystallinity with the crystallization time was analyzed by the Avrami equation. For nonisothermal studies, the Kissingers theory was employed and the crystallization activation energy was calculated. The results showed that the crystallization temperature shifted to a higher temperature range when calcium pimelate was added. The alpha crystal form of polypropylene nanocomposite was suppressed, by the additions of calcium pimelate, while beta crystallization reaction was accelerated.

Effect of Arenga Pinnata “Ijuk” Fiber as Nucleating Agent on Crystallization Kinetics of Impact Polypropylene Copolymer

2018 ◽  
Vol 923 ◽  
pp. 56-60 ◽  
Author(s):  
Mochamad Chalid ◽  
Evana Yuanita ◽  
Ghiska Ramahdita ◽  
Jaka Fajar Fatriansyah
Keyword(s):  
Crystal Growth ◽  
Crystallization Kinetics ◽  
Nucleating Agent ◽  
Avrami Equation ◽  
Nucleating Agents ◽  
Impact Polypropylene Copolymer ◽  
Kinetics Of

Impact Polypropylene Copolymer (IPC) is one of the PP type which is widely used. IPC was made with addition of ethylene in PP which decreases PP crystallinity. Many efforts have been made to improve the properties of PP crystallinity by addition of nucleating agents. In this study, we use Arenga Pinnata “Ijuk” fiber as PP nucleating agent. In order to determine the effect of “Ijuk” fiber as nucleating agents in kinetics aspect, we used DSC measurement based on Avrami equation. The results showed that the addition of ijuk decreases crystallizationhalf timeand dimension of crystal growth which indicate the effects of “Ijuk” fiber as a nucleating agent.

Crystallization Behavior and Growing Process of Rutile Crystals in Ti-Bearing Blast Furnace Slag

2016 ◽  
Vol 35 (8) ◽  
pp. 787-797
Author(s):  
Wu Zhang ◽  
Li Zhang ◽  
Yuhai Li ◽  
Xin Li
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Crystallization Process ◽  
Elevated Temperatures ◽  
Avrami Equation ◽  
X Ray Diffraction ◽  
Experimental Parameters ◽  
Kinetics Of ◽  
Crystal Seed ◽  
Furnace Slag

AbstractThe aim of the present work is to elucidate crystallization and growing process of rutile crystals in Ti-bearing blast furnace slag. The samples were taken from the liquid slag and quenched at once at elevated temperatures in order to analyze phase transaction of titanium and grain size of rutile crystals. Crystallization and growing kinetics of rutile crystals under elevated temperature conditions were calculated, and the crystallization process of rutile crystals under isothermal conditions was expressed by Avrami equation. The effects of experimental parameters, such as experimental temperatures, SiO2 addition, cooling rate, crystal seed addition and oxygen flow, were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), the optimal conditions for rutile crystals to grow up were obtained. Distribution and movement state of rutile crystals in the slag were analyzed.

Isothermal Crystallization Kinetics of Poly(phenylene Sulfide)/ZnO Composites

2012 ◽  
Vol 535-537 ◽  
pp. 243-246 ◽  
Author(s):  
Zhong Hou Zhang ◽  
Wen Xin Zhou ◽  
Ya Dong Li ◽  
Chun Mian Yan
Keyword(s):  
Heterogeneous Nucleation ◽  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Nucleating Agent ◽  
Avrami Equation ◽  
Crystallization Time ◽  
Nano Zno ◽  
Kinetics Of ◽  
Phenylene Sulfide

Poly (phenylene sulfide) (PPS)/nano-ZnO composites were prepared by DAKA miniature blending instrument. Isothermal crystallization behavior of PPS composites at 245°C, 250°C, 255°C and 260°C were investigated by means of DSC. The crystallization time of PPS composites is shorter than which of neat PPS at the same crystallization temperature. The Avrami equation was used to analyze DSC data. Results showed that neat PPS is homogeneous nucleation at lower crystallization temperature, which is heterogeneous nucleation at higher crystallization temperature contrarily. PPS/nano-ZnO composites are heterogeneous nucleation at various crystallization temperature, nano-ZnO particles play a role of nucleating agent.

Study on the Isothermal Crystallization Kinetics of Polyvinyl Pyrrolidone/Polyamide 6 Blends

2012 ◽  
Vol 557-559 ◽  
pp. 1487-1491
Author(s):  
Shi Jie Zhang ◽  
Yi Wen Tang ◽  
Xin Li Yang ◽  
Li Hua Cheng
Keyword(s):  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Crystallization Process ◽  
Crystallization Rate ◽  
Polyamide 6 ◽  
Polyvinyl Pyrrolidone ◽  
Avrami Equation ◽  
Intermolecular Hydrogen Bonds ◽  
Isothermal Crystallization Kinetics ◽  
Kinetics Of

The Avrami equation was used in the study of the isothermal crystallization kinetics of Polyvinyl pyrrolidone/Polyamide 6 Blends. The addition of PVP can hinder the PA6 crystallization process, increase the crystallization half-time and make the crystallization rate decrease. The molecular entanglements and intermolecular hydrogen bonds between PA6 and PVP chains exert some influence also.

Nonisothermal crystallization kinetics of polybutene-1 containing nucleating agent with acid amides structure

2014 ◽  
Vol 34 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Yongxian Zhao ◽  
Junyi Chen ◽  
Lei Han ◽  
Le Zhao
Keyword(s):  
Crystallization Process ◽  
Crystallization Rate ◽  
Nucleating Agent ◽  
Mass Ratio ◽  
Scanning Calorimetry ◽  
Nonisothermal Crystallization ◽  
Nucleation Effect ◽  
Activation Energy Of Crystallization ◽  
Nonisothermal Crystallization Kinetics ◽  
Kinetics Of

Abstract The nonisothermal crystallization behaviors of virgin isotactic polybutene-1 (iPB-1) and iPBn (iPB-1 containing a nucleating agent that owns acid amides structure; iPB/Mult920=100/0.5, mass ratio) were studied by means of differential scanning calorimetry (DSC). Modified Avrami theories (Ozawa method) and Mo method were used to analyze the DSC date. The results show that both methods are suitable to describe the crystallization process of iPB-1 and iPBn. Addition of 0.5% (mass ratio) nucleating agent can give rise to the nucleation effect, which increases the crystallization temperature (Tc) and the rate of crystallization of iPB-1, decreases the activation energy of crystallization (ΔE), and increases the crystallization rate of iPB-1 under the actual conditions.

Isothermal Crystallization Kinetics of Poly (Phenylene Sulfide)/TiO2 Composites

2011 ◽  
Vol 284-286 ◽  
pp. 1909-1912 ◽  
Author(s):  
Zhong Hou Zhang ◽  
Guang Xiu Cao ◽  
Ying Ying Li ◽  
Chun Mian Yan
Keyword(s):  
Heterogeneous Nucleation ◽  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Nucleating Agent ◽  
Avrami Equation ◽  
Crystallization Time ◽  
Isothermal Crystallization Kinetics ◽  
Kinetics Of ◽  
Phenylene Sulfide

Poly (phenylene sulfide) (PPS)/nano-TiO2composites were prepared by DAKA miniature blending instrument. Isothermal crystallization behavior of PPS composites at 245°C, 250°C, 255°C and 260°C were investigated by means of DSC. The crystallization time of PPS composites is shorter than which of neat PPS at the same crystallization temperature. The Avrami equation was used to analyze DSC data. Results showed that neat PPS is homogeneous nucleation at lower crystallization temperature, which is heterogeneous nucleation at higher crystallization temperature contrarily. PPS/nano-TiO2composites are heterogeneous nucleation at various crystallization temperature, nano-TiO2particles play a role of nucleating agent.

scholarly journals Starch Retrogradation in Rice Cake: Influences of Sucrose Stearate and Glycerol

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1737
Author(s):  
Seon-Min Oh ◽  
Hee-Don Choi ◽  
Hyun-Wook Choi ◽  
Moo-Yeol Baik
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Ester ◽  
Acid Ester ◽  
Coefficient Of Determination ◽  
Avrami Equation ◽  
Relative Crystallinity ◽  
Rice Cake ◽  
Sucrose Fatty Acid Ester ◽  
Kinetics Of ◽  
Rice Cakes

Retrogradation properties and kinetics of rice cakes with the addition of glycerol (GLY) and sucrose fatty acid ester (SE) were investigated. In hardness, both rice cakes with glycerol (RGLY) and rice cakes with sucrose fatty acid ester (RSE) showed lower initial hardening compared with the control for up to 5 days. X-ray diffraction (XRD) pattern of RSE showed a B+V-type pattern, and the relative crystallinity showed that GLY and SE lowered the initial and final crystallization of rice cake. Both GLY and SE affected the retrogradation enthalpy, glass transition temperature, and ice melting enthalpy in differential scanning calorimeter (DSC). However, 1H NMR relaxation time (T2) of rice cake decreased regardless of additives. From these results, the addition of glycerol and sucrose stearate inhibits the retrogradation process of rice cakes, which will solve industrial problems. Applying the Avrami equation for retrogradation kinetics of rice cake was suitable in XRD and DSC with high coefficient of determination (0.9 < R2). Meanwhile, the other retrogradation index improved the R2 when the exponential rise to maximum equation was used. This suggests that there is an alternative of Avrami equation to predict the retrogradation.

scholarly journals Non-Isothermal Crystallization Kinetics of Poly(Ethylene Glycol)–Poly(l-Lactide) Diblock Copolymer and Poly(Ethylene Glycol) Homopolymer via Fast-Scan Chip-Calorimeter

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1156
Author(s):  
Dejia Chen ◽  
Lisha Lei ◽  
Meishuai Zou ◽  
Xiaodong Li
Keyword(s):  
Ethylene Glycol ◽  
Heterogeneous Nucleation ◽  
Isothermal Crystallization ◽  
Crystallization Process ◽  
Poly Ethylene Glycol ◽  
Ozawa Method ◽  
Isothermal Crystallization Kinetics ◽  
Fast Cooling ◽  
Poly Ethylene ◽  
Kinetics Of

The non-isothermal crystallization kinetics of double-crystallizable poly(ethylene glycol)–poly(l-lactide) diblock copolymer (PEG-PLLA) and poly(ethylene glycol) homopolymer (PEG) were studied using the fast cooling rate provided by a Fast-Scan Chip-Calorimeter (FSC). The experimental data were analyzed by the Ozawa method and the Kissinger equation. Additionally, the total crystallization rate was represented by crystallization half time t1/2. The Ozawa method is a perfect success because secondary crystallization is inhibited by using fast cooling rate. The first crystallized PLLA block provides nucleation sites for the crystallization of PEG block and thus promotes the crystallization of the PEG block, which can be regarded as heterogeneous nucleation to a certain extent, while the method of the PEG block and PLLA block crystallized together corresponds to a one-dimensional growth, which reflects that there is a certain separation between the crystallization regions of the PLLA block and PEG block. Although crystallization of the PLLA block provides heterogeneous nucleation conditions for PEG block to a certain extent, it does not shorten the time of the whole crystallization process because of the complexity of the whole crystallization process including nucleation and growth.

scholarly journals Morphology and crystallization kinetics of Rubber-modified Nylon 6 Prepared by Anionic In-situ Polymerization

2020 ◽  
Vol 27 (1) ◽  
pp. 204-215
Author(s):  
Hongkai Zhao ◽  
Dengchao Zhang ◽  
Yingshuang Li
Keyword(s):  
Crystallization Kinetics ◽  
In Situ Polymerization ◽  
Good Description ◽  
Nylon 6 ◽  
Avrami Equation ◽  
Infrared Analysis ◽  
Chain Segment ◽  
The Impact ◽  
Kinetics Of

AbstractIn this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.

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