{"title":"聚丙烯无规共聚物中β晶体和橡胶相的协同增韧作用","authors":"","doi":"10.1016/j.polymer.2024.127543","DOIUrl":null,"url":null,"abstract":"<div><p>Polypropylene random copolymer (PPR) is in high demand for pipelines due to its comprehensively brittle-ductile balance. It is a multiphase polymer composed of crystalline phases and rubbery phases in which improving the quantities of ductile β-crystals can effectively toughen PPR. However, the influence of β-crystallization on the aggregation of rubbery phases and their collaboration for toughening are still not well elucidated. In this work, the toughening mechanism of PPR/iPP/β-NA composites were illustrated by manipulating the crystallization and phase separation behaviors using different molecular weight of isotactic polypropylene (iPP) and β-nucleating agent (β-NA). A high relative β-crystal content (K<sub>β</sub>) was obtained in PPR/iPP/β-NA composites and the influence of molecular weight of iPP on crystal structures of PPR/iPP/β-NA composites was investigated via differential scanning calorimetry (DSC) and x-ray diffraction (XRD). The phase separation behaviors were then studied using rheological measurements and scanning electron microscope (SEM). The impact behaviors of PPR/iPP/β-NA composites with similar crystal structures but different size of rubbery particles were demonstrated. It was found that crystallization of PPR into β-crystal promoted the phase separation process and the resulting rubbery particle size. The deformation of large rubbery particles induced small wavy cracks at the fracture surface other than layered cracks for small rubbery particles. This work basically introduces the toughening mechanism from collaboration of β-crystals and rubbery phases in polypropylene random copolymers and provides a new method for fabricating high toughness PPR pipe.</p></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":null,"pages":null},"PeriodicalIF":4.1000,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Collaboration of β-crystals and rubbery phases in polypropylene random copolymer for toughening\",\"authors\":\"\",\"doi\":\"10.1016/j.polymer.2024.127543\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Polypropylene random copolymer (PPR) is in high demand for pipelines due to its comprehensively brittle-ductile balance. It is a multiphase polymer composed of crystalline phases and rubbery phases in which improving the quantities of ductile β-crystals can effectively toughen PPR. However, the influence of β-crystallization on the aggregation of rubbery phases and their collaboration for toughening are still not well elucidated. In this work, the toughening mechanism of PPR/iPP/β-NA composites were illustrated by manipulating the crystallization and phase separation behaviors using different molecular weight of isotactic polypropylene (iPP) and β-nucleating agent (β-NA). A high relative β-crystal content (K<sub>β</sub>) was obtained in PPR/iPP/β-NA composites and the influence of molecular weight of iPP on crystal structures of PPR/iPP/β-NA composites was investigated via differential scanning calorimetry (DSC) and x-ray diffraction (XRD). The phase separation behaviors were then studied using rheological measurements and scanning electron microscope (SEM). The impact behaviors of PPR/iPP/β-NA composites with similar crystal structures but different size of rubbery particles were demonstrated. It was found that crystallization of PPR into β-crystal promoted the phase separation process and the resulting rubbery particle size. The deformation of large rubbery particles induced small wavy cracks at the fracture surface other than layered cracks for small rubbery particles. This work basically introduces the toughening mechanism from collaboration of β-crystals and rubbery phases in polypropylene random copolymers and provides a new method for fabricating high toughness PPR pipe.</p></div>\",\"PeriodicalId\":405,\"journal\":{\"name\":\"Polymer\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.1000,\"publicationDate\":\"2024-08-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Polymer\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0032386124008796\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"POLYMER SCIENCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Polymer","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0032386124008796","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
Collaboration of β-crystals and rubbery phases in polypropylene random copolymer for toughening
Polypropylene random copolymer (PPR) is in high demand for pipelines due to its comprehensively brittle-ductile balance. It is a multiphase polymer composed of crystalline phases and rubbery phases in which improving the quantities of ductile β-crystals can effectively toughen PPR. However, the influence of β-crystallization on the aggregation of rubbery phases and their collaboration for toughening are still not well elucidated. In this work, the toughening mechanism of PPR/iPP/β-NA composites were illustrated by manipulating the crystallization and phase separation behaviors using different molecular weight of isotactic polypropylene (iPP) and β-nucleating agent (β-NA). A high relative β-crystal content (Kβ) was obtained in PPR/iPP/β-NA composites and the influence of molecular weight of iPP on crystal structures of PPR/iPP/β-NA composites was investigated via differential scanning calorimetry (DSC) and x-ray diffraction (XRD). The phase separation behaviors were then studied using rheological measurements and scanning electron microscope (SEM). The impact behaviors of PPR/iPP/β-NA composites with similar crystal structures but different size of rubbery particles were demonstrated. It was found that crystallization of PPR into β-crystal promoted the phase separation process and the resulting rubbery particle size. The deformation of large rubbery particles induced small wavy cracks at the fracture surface other than layered cracks for small rubbery particles. This work basically introduces the toughening mechanism from collaboration of β-crystals and rubbery phases in polypropylene random copolymers and provides a new method for fabricating high toughness PPR pipe.
期刊介绍:
Polymer is an interdisciplinary journal dedicated to publishing innovative and significant advances in Polymer Physics, Chemistry and Technology. We welcome submissions on polymer hybrids, nanocomposites, characterisation and self-assembly. Polymer also publishes work on the technological application of polymers in energy and optoelectronics.
The main scope is covered but not limited to the following core areas:
Polymer Materials
Nanocomposites and hybrid nanomaterials
Polymer blends, films, fibres, networks and porous materials
Physical Characterization
Characterisation, modelling and simulation* of molecular and materials properties in bulk, solution, and thin films
Polymer Engineering
Advanced multiscale processing methods
Polymer Synthesis, Modification and Self-assembly
Including designer polymer architectures, mechanisms and kinetics, and supramolecular polymerization
Technological Applications
Polymers for energy generation and storage
Polymer membranes for separation technology
Polymers for opto- and microelectronics.