Effect of nucleating agent supported on zeolite via the impregnation on the crystallization ability of isotactic polypropylene and its mechanism

Abstract

Addition of an α‐nucleating agent is the simple and effective method to increase nucleation efficiency of isotactic polypropylene (iPP). However, severe agglomeration and poor dispersibility of sodium 2,2′‐methylene‐bis(4,6‐di‐tertbutylphenyl) phosphate (NA11) decrease the nucleation efficiency in the iPP, and much more nucleating agent is needed to maintain the nucleating property. As a result, it becomes the key how to decrease the size of NA11 and increase the nucleating property. In this paper, zeolite 4A (Z4A) was firstly supported by NA11 through solution impregnation, and NA11 was dispersed by Z4A depending on the dispersion of zeolite as carrier for the second component. Then, the dispersed NA11 system (NA11‐Z4A) exhibited a superior nucleation behavior during the crystallization of the iPP matrix when it was used with iPP together. The isothermal and nonisothermal crystallization kinetics indicated that the NA11‐Z4A/iPP system had the best crystallization effect. Polarized optical microscopy (POM) and scanning electron microscopy (SEM) analyses showed that the size of NA11 decreased obviously when it was adsorbed on the surface of Z4A, which leads a better dispersibility of the nucleating agent and thus an accelerated nucleation process in the iPP matrix. In the end, the mechanism for the excellent dispersibility of NA11‐Z4A, which was based on hydrogen bonding between NA11 and Z4A, was confirmed by Fourier‐transform infrared spectroscopy (FTIR). Based on the research work, the solution impregnation strategy can potentially be applied to other systems to inhibit the agglomeration and improve the dispersibility of additives in iPP.

Continuous‐/Micro‐Flow Reactions Using Highly Electrophilic PCl3 and POCl3

“…In 2021, Xin et al. reported a synthesis of 2,2’‐methylene‐bis(4,6‐di‐ tert ‐butylphenol) phosphate ( 17 a ) that is useful as a plastic nucleating agent and a fine chemical [27] . Phosphate 17 a was synthesized from POCl 3 and 2,2’‐methylene‐bis(4,6‐di‐ tert ‐butyl) phenol ( 16 a ).…”

“…In 2021, Xin et al reported a synthesis of 2,2'-methylenebis(4,6-di-tert-butylphenol) phosphate (17 a) that is useful as a plastic nucleating agent and a fine chemical. [27] Phosphate 17 a was synthesized from POCl 3 and 2,2'-methylene-bis(4,6-di-tertbutyl) phenol (16 a). In this reaction, the in situ generated hydrogen chloride was trapped by Et 3 N. In order to avoid an undesired clogging of the flow reactor by precipitations of the amine hydrochloride salts, solvents were preliminarily screened using a batch reactor.…”

Thermal and Kinetic Research on a Highly Exothermic Condensation Reaction by Powerful Calorimeters

“…2,2′-Methylene-bis­(4,6-di- tert -butylphenol) phosphate chloride is the intermediate of many plastics nucleating agents such as NA-40, NA-45, and NA-71, which are considered as extremely important chemicals in the fine chemical industry and have a broad application in the modified polypropylene. − Generally, 2,2′-methylene-bis­(4,6-di- tert -butylphenol) phosphate chloride ( 2 ) can be synthesized by a highly exothermic homogeneous condensation reaction between 2,2′-methylene-bis­(4,6-di- tert -butyl) phenol ( 1 ) and POCl 3 with triethylamine as the acid-binding agent base, along with the formation of triethylamine hydrochloride ( 3 ) (Scheme ). − An obvious thermal effect appeared upon the contact of all the reactants, so potential danger must be taken into account especially when the heat transfer capacity of the reactor is insufficient.…”

The Influence of Metal Lithium and Alkyl Chain in the Nucleating Agent Lauroyloxy-Substituted Aryl Aluminum Phosphate on the Crystallization and Optical Properties for iPP

“…Kimura et al [13] proposed, for the first time, that the synergistic effect o APAl-OH and lithium laurate can reduce the haze of PP from 32% to 5%. As a kind o additive nucleating agent, NA-21 is difficult to disperse in the iPP system because of the presence of strong polar phosphate compounds in its components [14]. At present, many studies have been devoted to improving the dispersion of the APs nucleating agents in the iPP matrix [15][16][17].…”