Influence of β-Nucleators on iPP Crystallization and Morphology

Xiong, Fen; Guan, Rong; Xiao, Zhaoxin; Xiang, Bin; Lu, Deping

doi:10.1080/03602550601152739

Cited by 10 publications

(9 citation statements)

References 27 publications

(34 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, Dou and Lu19–21 have found that some metallic salts of malonic acid possess β‐nucleating ability. Some complexes of rare earth metal (denoted as WBG) can also induce the formation of the β‐form 22–24. Recently, Zhang et al25 and Yang et al26 showed that the mixture of nano‐CaCO 3 and pimelic acid can be used as a two‐component β‐NA.…”

Section: Introductionmentioning

confidence: 99%

Crystallization of isotactic polypropylene in the presence of a β‐nucleating agent based on a trisamide of trimesic acid

Varga

Stoll

Menyhárd

et al. 2011

J of Applied Polymer Sci

View full text Add to dashboard Cite

Tris-2,3-dimethyl-hexylamide of trimesic acid (TATA) is an new type of b-nucleating agent for isotactic polypropylene (iPP). The crystallization, melting characteristics, and the supermolecular structure of iPP nucleated with TATA were studied on the samples crystallized under nonisothermal and isothermal conditions. The b-nucleating ability of TATA was rather high even at low concentration. It was established that TATA possessed dual nucleating ability generating samples with mixed (a and b) polymorphic compositions. The b-content showed an maximum value at low concentrations (10-100 ppm) of TATA. The b-content decreased with increasing concentration of TATA in the higher concentration range. The highest b-content (about 80%) was achieved at the crystallization temperature T c ¼ 110-120 C at low concentration of TATA. The crystallization curves registered at constant cooling rate or under isothermal condition have a single peak in spite of the formation of two polymorphic modifications. The crystallization isotherms cannot be linearized according to the Avrami equation because of simultaneous crystallization of the a-and b-forms, having different nucleation and growth rate. It was also found that the b-content increased with increasing conversion during isothermal crystallization because of the higher growth rate of the b-phase. The b-phase formed in the presence of TATA consist of lamellar crystallites. In the early stage of the crystallization, hedritic structure is formed.

show abstract

Section: Introductionmentioning

confidence: 99%

Crystallization of isotactic polypropylene in the presence of a β‐nucleating agent based on a trisamide of trimesic acid

Varga

Stoll

Menyhárd

et al. 2011

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…In order to exclude the molecular weight effect, which is also present for the impact resistance of non-nucleated iPP homopolymers [62], the relative value of Δ NIS can be calculated by Equation (14). As Figure 7 shows, even in the worst-case increases by 300% can be achieved with CGNA-7588, while at least for the SSC-PPH a negative effect results from nucleation with WBG.…”

Section: Resultsmentioning

confidence: 99%

“…All mechanical parameters have been determined according to ISO standards using 10+2 measurements, discarding the extremes and giving relative standard deviations in the range of 5%. The relative effect of β-nucleation on impact strength (Δ NIS ) was calculated based on the following formula 14: (14) where NIS BN stands for the value of the β-nucleated polymer while NIS NN stands for the value of the nonnucleated base polymer. The calculation of Δ NIS was done for the values determined at 23°C.…”

Section: Experimental Workmentioning

confidence: 99%

“…Several working groups evaluated the performance of this β-nucleating agent alone [7][8][9][10][11][12][13], varying dispersion mode, cooling history, and base polymer type. Comparisons to α-nucleation [14][15][16][17][18] or other types of β-nucleating agents were done as well. The latter was done in comparison to DCHT (N,N′-dicyclohexyl-terephthalamide) by Xiao et al [19] and Fu et al [20].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

β-Nucleation of isotactic polypropylene: Chain structure effects on the effectiveness of two different nucleating agents

Wang¹,

Gahleitner²,

Gloger³

et al. 2020

Express Polym. Lett.

View full text Add to dashboard Cite

Of all crystal modifications of isotactic polypropylene (iPP), the β-phase has received particular attention in both academia and industry because of the toughness increase resulting from its formation. Several novel nucleating agents have been presented and studied in recent years, most prominently the 'lanthanum complex' WBG. The majority of these studies are based only on one type of iPP, mostly an iPP homopolymer, despite the fact that chain irregularities are known to affect β-phase formation negatively. In the present study, several different iPP homo-and copolymers based on Ziegler-Natta and single-site catalysts differing mostly in chain defect concentration were used to evaluate the sensitivity of a 'reference' nucleating agent, quinacridonequinone, as well as WBG to chain structure effects. The results in terms of crystal structure, as well as mechanics, indicate a much greater sensitivity of WBG, resulting in a massively reduced β-phase formation for SSC-iPP hompolymers and ZN-iPP random copolymers with ethylene. An increase of γ-phase content in nucleation of the polymers with least regular chain structure hints at some duality for WBG as also observed for other β-nucleating agents before.

show abstract

“…Some special techniques can be used to obtain the iPP with relatively high levels of b-phase, such as the temperature gradient method [11] , flow-induced crystallization [12][13][14] and adding specific nucleating agent [15][16][17][18][19] . Among them, the addition of some b-nucleating agents is an efficient and accessible method to obtain the iPP with relatively high level of b-phase.…”

Section: Study Of Micro-injectionmentioning

confidence: 99%

Study of Micro-Injection Moulding: Factors Affecting the Content of the β-phase in Isotactic Polypropylene with β-nucleating Agent

Zhang

Liu

et al. 2012

Polymer-Plastics Technology and Engineering

View full text Add to dashboard Cite

The special processing conditions of micro-injection moulding will affect the micro-structure of polymer microparts processed by micro-injection moulding. In this article, two-dimensional wideangle X-ray diffraction (2D-WAXD) and differential scanning calorimetry (DSC) were used to study the influence of nucleating agent concentration, mould temperature and injection pressure on content of the b-phase in isotactic polypropylene (iPP) with b-nucleating agent in micro-injection moulding. It was found that the high shear stress during micro-injection moulding could induce the formation of b-phase crystals in pure iPP, but which could restrain the formation of b-phase crystals in iPP with b-nucleating agent. The b-crystal content in micro-injection moulded samples decreased continuously with increasing the mould temperature from 130 C to 160 C. Besides, the shear stress that could restrain the nucleating efficiency of b-nucleating agent in b-nucleated iPP increased with the rise of the injection pressure and resulted in the decrease of b-phase crystals in the sample.

show abstract

Influence of β-Nucleators on iPP Crystallization and Morphology

Cited by 10 publications

References 27 publications

Crystallization of isotactic polypropylene in the presence of a β‐nucleating agent based on a trisamide of trimesic acid

Crystallization of isotactic polypropylene in the presence of a β‐nucleating agent based on a trisamide of trimesic acid

β-Nucleation of isotactic polypropylene: Chain structure effects on the effectiveness of two different nucleating agents

Study of Micro-Injection Moulding: Factors Affecting the Content of the β-phase in Isotactic Polypropylene with β-nucleating Agent

Contact Info

Product

Resources

About