有机化工与催化 酰胺型β成核剂对聚丙烯性能的影响

通过在抗冲聚丙烯基础树脂中添加自主研制的酰胺型高效β成核剂FB-1,在提高聚丙烯耐热温度的同时有效提高聚丙烯的冲击强度,介绍β成核剂的复配及超细化,研究β成核剂含量对共聚聚丙烯EPS30R冲击强度的影响,考察β成核剂改性聚丙烯的加工稳定性及β成核剂改性共聚聚丙烯的结晶行为。结果表明,加入成核剂后,聚丙烯冲击性能显著提高,β晶型聚丙烯的热稳定性及反复加工性能良好, FB-1成核剂能有效促进聚丙烯中β晶型的形成,而且β成核剂只改变β晶型含量,不改变其微观结构,β成核剂对聚丙烯中的α晶型没有影响。     

β成核剂与无机填料对聚丙烯力学性能的影响

无机填料可以提高聚丙烯的刚性、硬度、抗化学性、尺寸稳定性和气体阻隔性,同时减少聚合物的用量,降低产品成本。滑石粉和碳酸钙是聚丙烯复合材料中大量使用的两种填料。主要研究β成核剂和无机填料对聚丙烯成核效应的协同作用,考察经β成核剂FB-1分别与无机填料滑石粉和碳酸钙共同改性的聚丙烯力学性能。     

无机成核剂对等规聚丙烯结晶的影响

论述了无机类成核剂滑石粉、碳酸钙、云母、硅灰石、玻璃微珠和二氧化硅以及其他无机填料对等规聚丙烯(IPP)结晶的影响,并总结了无机填料作为α-成核剂或者β成核剂对PP性能的影响。     

聚丙烯成核剂的研究进展

综述了近年来聚丙烯用无机成核剂(如滑石粉、碳酸钙、云母金属的氧化物及氢氧化物)和有机类成核剂(如缩醛类成核剂、磷酸盐类成核剂、松香型成核剂和酰胺类成核剂)的研究进展。第四代山梨醇缩醛类成核剂可使聚丙烯透明度提高50%,获得高透明聚丙烯;松香型成核剂和酰胺类成核剂是近年新开发的成核剂,单独使用或与其他成核剂复配使用,可提高聚丙烯成核效率;其他物质(如单甘油锌、单甘油钴、单甘油钙、勃母石)也可以用作聚丙烯成核剂。     

有机成核剂改性聚丙烯的研究

研究了无机成核剂滑石粉和3种有机成核剂NAA-A,NAP-B,HPN-C对聚丙烯2500H性能的影响。结果表明:有机成核剂对聚丙烯的成核作用明显好于滑石粉;添加有机成核剂NAA-A和HPN-C的聚丙烯中,橡胶粒子的数量更多且其尺寸和分布均匀性更好,晶粒尺寸也最为细小;有机成核剂改性的聚丙烯的弯曲应力、弯曲模量、拉伸屈服应力、常低温缺口冲击强度也都有所提高,成核剂HPN-C使聚丙烯上述性能提高最多,而滑石粉改性聚丙烯仅仅弯曲性能较好。     

改性聚丙烯收缩率的研究

讨论了矿物填料（如滑石粉、碳酸钙等）及玻璃纤维作为无机填料,乙烯-辛烯共聚物（POE）、线形低密度聚乙烯（PE-LLD）改性料及成核剂对聚丙烯（PP）收缩率的影响。结果表明,无机填料均能较明地显改善PP的收缩率,其中玻璃纤维影响较明显,添加30 %（质量分数,下同）玻璃纤维时PP收缩率由1.67 %下降到0.34 %,并且收缩率随填料填充量的增加而减小;POE、PE-LLD及成核剂的加入也能改善PP的收缩情况,且随着含量的增加收缩率变小,并且POE改善效果较PE-LLD更明显,当POE添加30 %时,PP的收缩率从1.67 %下降到1.16 %,当PE-LLD添加 30 %时,PP的收缩率从1.67 %下降到1.39 %;成核剂的加入在降低PP收缩率的情况下还能加快PP的结晶速率。     

β成核剂/无机填料共同作用对PP结晶行为的影响

将云母和硅美钙晶须作为无机填料,分别与稀土成核剂共同加入聚丙烯(PP)中,考察复合填充体系(填料-成核剂)对PP结晶行为的影响。结果表明,云母和晶须都能够作为聚丙烯的异相成核剂促进结晶,三元复合材料体系最终的结晶形貌、晶型含量比例等结晶性能是由无机填料与成核剂相互竞争所决定。云母的成核效率较低,加入高效的成核剂后其成核作用被抑制;而晶须的成核能力较强,与成核剂一同添加,两者能够共同促进聚丙烯结晶。     

聚甲醛结晶成核剂研究进展

对国内外聚甲醛(POM)结晶成核剂进行了分类。概述了碳酸钙、滑石粉、硅藻土等无机成核剂,碳纳米管、聚酰胺、均聚甲醛等有机成核剂,氧化镁、超细Fe粉等金属类成核剂及滑石粉/弹性体等复合成核剂对POM结晶性能和力学性能等的影响。对POM成核剂的开发提出了建议。     

聚丙烯增强改性的研究概况

聚丙烯(PP)增强改性的增强剂主要是纤维(玻璃纤维、碳纤维、天然纤维、芳纶纤维等)和无机填料(滑石粉、碳酸钙等)。对聚丙烯(PP)增强改性的机理,优缺点及应用进行了研究和探讨,并对其发展趋势进行了阐述。     

中国塑料专利

正专利名称:无机填料改性剂和改性无机填料及其制备方法和应用以及聚丙烯复合材料及其制备方法申请公布号:CN108059770A申请公布日:2018.05.22本发明涉及聚合材料领域,具体提供了一种无机填料改性剂,该改性剂包括:界面增容剂和β成核剂,其中,β成核剂与界面增容剂的质量比为0.04:1~2:1。本发明提供了一种改性无机填料及其制备方法和应用,该方法包括:将无机填料、界面增容剂和β成核剂混合     

碳酸钙在复合改性中的应用

无机填料碳酸钙在聚丙烯复合体系中的应用,研究了碳酸钙的加入对聚丙烯光学性能、分散性、力学性能中的冲击强度的影响,同时深入分析了无机填料对聚丙烯复合体系的增强增韧机理。     

An investigation on the mechanical and dynamic rheological properties of single and hybrid filler/polypropylene composites based on talc and calcium carbonate

Some results of experiments on the mechanical and rheological properties of mineral filled polypropylene were presented. Single filler and hybrid filler composites of talc and calcium carbonate (CaCO₃) were prepared in a co‐rotating twin‐screw extruder. The effect of filler type, filler content, and coupling agent on the mechanical and rheological properties of the polypropylene were studied. The coupling agent was maleic anhydride‐grafted polypropylene (PP‐g‐MA). It was found that the mechanical properties are affected by filler type, filler concentration, and the interaction between filler and matrix. The tensile strength of the composite is more affected by the talc while the impact strength is influenced mostly by CaCO₃ content. The elongation at break of PP/CaCO₃ composites was higher than that of PP/talc composites. The incorporation of coupling agent into PP/mineral filler composites increased the mechanical properties. Rheological properties indicated that the complex viscosity and storage modulus of talc filled samples were higher than those of calcium carbonate filled samples while the tan δ was lower. The rheological properties of hybrid‐filler filled sample were more affected by the talc than calcium carbonate. The PP‐g‐MA increased the complex viscosity and storage modulus of both single and hybrid composites. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers     

Characterization of melt‐compounded and masterbatch‐diluted polypropylene composites filled with several fillers

The effect of various fillers on the mechanical, barrier, and flammability properties of polypropylene (PP) was studied. PP was filled with 4 wt% of nano‐sized calcium carbonate, titanium dioxide, organoclay, and multiwalled carbon nanotube (MWCNT). For comparison, micron‐sized calcium carbonate was also studied. Two‐step masterbatch dilution approach of the composites suggested no or only minor improvements in Young's modulus and tensile yield strength, whereas their ductility decreased compared to coupling agent‐modified PP matrix. The water vapor transmission results of filled films showed increased permeability compared to their coupling agent‐modified counterpart. Oxygen permeability, however, decreased for the composites. The MWCNT‐filled matrix showed the highest barrier and fire performance, attributed mainly to its higher filler volume content, but also other reasons such as the effect of filler dispersion, composite's thermal stability, and polymer crystallinity were discussed.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

Nucleation and crystallization of polypropylene by mineral fillers: relationship to impact strength

The mechanical properties of mineral-filled polypropylene (PP) are determined not only by the size, shape and modulus of the filler particles, but also by microstructure. For example, poor impact strength is correlated with a high capacity for nucleation of crystallization. In the present study, optical microscopy has been used to measure the growth rate of spherulites in PP. In tandem with this, isothermal d.s.c. measurements have been made of the crystallization of the PP filled with talc, calcium carbonate and stearate-coated carbonate at different loading levels. Computer simulation of spherulite growth has been used to derive the number of nucleating sites per unit volume of polymer and, using surface area measurements, the number of sites per unit area of mineral surface was obtained. Values for talc were, as expected, considerably higher than those for carbonate (and especially coated carbonate) fillers. The presence of filler affects not only the nucleation and kinetics of the crystallization process but also the crystallinity and orientation indices and the proportion of β-phase crystallites present. The connection between these factors and impact strength is discussed. It is concluded that impact properties are determined by inter alia crack pinning and blocking by filler particles, stress concentrations at the edges of the filler particles, and the nucleating ability of the filler.     

Thermo-mechanical and mechanical behavior of hybrid isotactic polypropylene glass fiber reinforced composites (GFRC) modified with calcium carbonate (CaCO3)

The study investigates the thermo-mechanical properties of isotactic polypropylene (iPP) hybrid composites in reference to various amounts of particle- and fiber-shaped inorganic fillers. Three grades of hybrid composites were prepared as a function of filler amount: 5, 10, and 20 wt% and different ratios of glass fiber (GF) and calcium carbonate (CaCO₃). The main objective is to describe the relationship between the hybridization efficiency and mechanical performance of polypropylene-based composites. The analysis of the thermo-mechanical properties of the composites shows that both the total amount of the filler and the ratio of GF and CaCO₃ clearly influence the properties of the composites. Hybrid composites with the highest amount of the GF display improved thermo-mechanical stability. The presence of well-dispersed CaCO₃ in the composites was found to improve elongation at break and Vicat softening temperature values. Even though it is glass fiber, which shows higher filler effectiveness and visibly reinforces the composite samples, causing an increase in tensile strength or reinforcing efficiency, replacing up to 50% of this filler with calcium carbonate does not result in a considerable deterioration of the properties of the material.     

Mechanical and thermal properties of talc and calcium carbonate filled polypropylene hybrid composites

The main aim of this work was to study and compare the mechanical and thermal properties of hybrid polypropylene (PP) composites and single‐filler PP composites. With two main types of mineral fillers—calcium carbonate (CaCO₃) and talc—PP composites of different filler weight ratios (talc/CaCO₃) were compounded with a twin‐screw extruder and then injection‐molded into dumbbell specimens with an injection‐molding machine. Tensile, flexural, and impact tests were performed to determine and compare the mechanical properties of the hybrid and single‐filler PP composites. A synergistic hybridization effect was successfully achieved; the flexural strength and impact strength were highest among the hybrids when the PP/talc/CaCO₃ weight ratio was 70:15:15. The nucleating ability of the fillers and its effects on the mechanical properties were also studied with differential scanning calorimetry. Because of the influence of talc as the main nucleating agent, the hybrid fillers showed significant improvements in terms of the nucleating ability, and this contributed to the increase in or retention of the mechanical properties of the hybrid composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3327–3336, 2004     

PVA对碳酸钙、淤泥/不饱和聚酯树脂体系增强的探讨

采用聚乙烯醇(PVA)对碳酸钙、淤泥进行改性并将其作为不饱和聚酯树脂填料。研究了PVA掺量对碳酸钙/不饱和聚酯树脂和淤泥/不饱和聚酯树脂体系力学性能的影响。采用IR、DSC和SEM探讨了PVA对这2类体系的改性机理。实验结果表明:加入5%PVA后,碳酸钙/树脂体系,淤泥/树脂体系弯曲强度分别提高了55.3%和58.4%。PVA对2种体系的改性增强效应均源于PVA与填料和树脂之间氢键的桥梁作用,氢键改善了无机填料与树脂的相容性,这与以往改性剂与碳酸钙反应生成酯酸钙固化物的机理是不同的。     

Investigation of the Influence of Fillers on the Properties of Poly(vinyl acetate) Adhesives

The properties of poly(vinyl acetate) compositions prepared as potential wood adhesives were investigated. The paper presents the results of the influence of various kinds of inorganic fillers based on calcium carbonate and alumino-silicate and an organic filler, starch, on the adhesive composition properties. The comparison among rheological behavior of the adhesive dispersions concerning the specific role of fillers were made. Mechanical and relaxation properties of the adhesive films could reveal the effect of filler characteristics on the polymer matrix. The significant influences of particle size distribution and specific surface area on the poly(vinyl acetate) adhesive composition were determined, along with other filler characteristics.     

Investigation of the Influence of Fillers on the Properties of Poly(vinyl acetate) Adhesives

The properties of poly(vinyl acetate) compositions prepared as potential wood adhesives were investigated. The paper presents the results of the influence of various kinds of inorganic fillers based on calcium carbonate and alumino-silicate and an organic filler, starch, on the adhesive composition properties. The comparison among rheological behavior of the adhesive dispersions concerning the specific role of fillers were made. Mechanical and relaxation properties of the adhesive films could reveal the effect of filler characteristics on the polymer matrix. The significant influences of particle size distribution and specific surface area on the poly(vinyl acetate) adhesive composition were determined, along with other filler characteristics.