耐划伤车用聚丙烯材料的研制及应用

研究了耐划伤剂、滑石粉粒径对聚丙烯(PP)材料耐划伤效果与力学性能的影响,通过测试划伤前后的色差来评价耐划伤剂对材料的耐划伤效果.结果表明,耐划伤剂增加了材料的表面润滑性;采用小粒径滑石粉改性材料的耐划伤性能优于采用大粒径滑石粉改性的材料.利用耐划伤PP开发出的汽车内饰件被成熟应用于通用NGS308车型.     

车用聚丙烯内饰材料耐划伤性能研究

采用衰减全反射红外光谱(ATR)研究酰胺类耐划伤剂在车用聚丙烯(PP)耐划伤内饰材料表面和内部的含量分布.ATR及十字划格实验结果表明,酰胺耐划伤剂能有效地迁移到材料表面,降低表面摩擦系数,且酰胺耐划伤剂在材料表面和内部的分布有所差异.ATR及扫描电子显微镜(SEM)证明车用PP耐划伤内饰材料呈皮芯结构,未加入耐划伤剂...     

纳米海泡石对车用聚丙烯表面性能的影响

采用熔融共混方法制得了聚丙烯(PP)/纳米海泡石复合材料,并考察了纳米海泡石对PP表面性能的影响。结果表明,纳米海泡石在PP基体中达到了纳米级的均匀分散。相同填料含量下,与滑石粉填充PP共混物相比,纳米海泡石填充PP共混物的耐划伤性更优,虎皮纹外观和熔接线外观更不明显。     

免喷涂外观美学树脂的应用

为了替代传统喷涂材料,制备了高性能免喷涂聚丙烯(PP)复合材料,该PP复合材料具有金属光泽的美学外观,减少喷涂工艺所带来的环境污染且降低成本。以PP树脂为基体,使用自制的颜料分散剂PDA–1和耐划伤剂SR–1制备具有优异耐划伤性的免喷涂PP复合材料。通过扫描电子显微镜观察颜料在树脂内部的分布,使用五指刮擦仪评估材料使用不同耐划伤剂的抗划伤性能。通过加入颜料分散剂PDA–1解决了免喷涂产品各向异性的缺陷,实现各向同性的免喷涂美学外观;自制的抗划伤剂SR–1具有优异的耐划伤性,满足汽车行业对材料的耐划伤需求(大众汽车标准PV3925)。     

耐染色填充聚丙烯的研制与应用

研制一种耐染色的填充聚丙烯(PP)改性材料,探讨了PP和填料种类对其耐染色性能的影响.结果表明,影响填充PP耐染色性能的主要因素是PP种类,均聚PP的效果最好,无规共聚PP次之,嵌段共聚PP最差;填料对填充PP的耐染色性能有较大影响,填料A的效果最好,填料B次之,填料C最差,填料质量分数不宜超过20%.提高PP的结晶温...     

汽车用耐刮擦改性聚丙烯的研制

制备了汽车用耐刮擦改性聚丙烯(PP),分析了不同耐刮擦滑爽剂、矿物填料、PP结晶度及增容剂等对材料耐刮擦性能的影响。结果表明,采用高结晶PP、较小粒径的矿物填料和反应型高聚硅氧烷制备的改性PP具有优异的耐刮擦性能,完全适用于汽车零部件。     

耐划伤剂对车用聚丙烯材料耐划伤和散发性能的影响

采用熔融共混挤出的方法,制备了聚丙烯/滑石粉/弹性体三元共混材料,并考察了两种耐划伤剂对材料耐划伤性能、散发性能和力学性能的影响。采用十字划伤仪和色差仪对材料在常温和热老化(102℃,168 h)条件下的耐划伤性能进行了评价;采用气味评定、顶空–气相色谱、挥发性有机化合物(VOC)袋子法以及雾度仪分别对添加两种耐划伤剂后材料的气味、总挥发性有机化合物(TVOC)以及VOC和雾度进行了测试。结果表明,采用酰胺类和有机硅类耐划伤剂可改善聚丙烯材料表面的耐划伤性能,常温下两者效果相当,但热老化后前者耐划伤性能消失,而后者仍具有良好的耐划伤性能。在散发性能方面,采用有机硅类耐划伤剂在气味等级、VOC、雾度等方面均优于酰胺类划伤剂。相对于酰胺类耐划伤剂,添加有机硅类耐划伤剂的材料韧性和熔体流动速率有所提升。通过使用有机硅类耐划伤剂制备了在耐划伤性能和散发性能上均满足材料要求的汽车零部件。     

车用聚丙烯复合材料耐划伤性能及黏滑现象

研究了车用聚丙烯复合材料耐划伤性能及黏滑现象。结果表明:划痕宽度越宽,耐划伤性能越差;黏滑现象是造成聚丙烯复合材料耐划伤性能降低的原因之一。黏滑运动造成材料移除,使材料表面破坏严重;要提高其耐划伤性能,必须降低或消除划伤过程的黏滑现象。     

硅酮耐划伤剂对车用聚丙烯内饰材料性能的影响

采用衰减全反射红外光谱(ATR)研究了硅酮耐划伤剂改性的车用聚丙烯材料表面和内部的含量分布。ATR及十字划格实验结果表明:硅酮耐划伤剂能均匀地分散在材料的表面和内部。随着硅酮耐划伤剂用量的增大,材料耐划伤性能相应提高。ATR及扫描电镜(SEM)证明车用聚丙烯耐划伤注塑材料成皮芯结构,严重划伤样品的划痕破坏了材料表层,出现黏滑现象,而加入硅酮耐划伤剂的改性材料划痕深度较浅,添加量超过4.5%时,材料划伤前后的色差△L<1。     

聚丙烯材料划伤耐久性能研究

通过在聚丙烯材料中添加不同种类耐划伤剂(S1,S2,A1,A2)的方法,结合不同皮纹形貌,对比测试了划伤材料的耐划伤效果,并对不同老化时间下聚丙烯材料的耐划伤性能进行了研究。选择两种不同形貌的皮纹(粗皮纹M和细皮纹U)进行了研究,结果表明:对于相同材料,M皮纹的耐划伤效果比U差。与硅类耐划伤剂相比,酰胺类划伤剂具有更好的耐划伤效果,其中A2耐划伤效果最好。延长样品放置时间,样品耐划伤效果提高。研究了150℃老化条件下不同材料的耐划伤剂的耐久性,发现老化条件下,不同耐划伤聚丙烯材料的耐划伤性能表现各不相同:含有硅类耐划伤剂(S1和S2)的聚丙烯材料的耐划伤性能先降低后提高,最终降低;含有酰胺类耐划伤剂(A1和A2)的聚丙烯材料耐划伤性能随老化时间延长明显变差。通过扫描电子显微镜(SEM)测试了不同耐划伤剂对材料表面的划痕特性的影响,发现使用耐划伤剂A2可以有效减轻在划伤过程中出现的发白现象。     

Scratch resistance of mineral‐filled polypropylene materials

Pigmented mineral‐filled polypropylene (PP‐PMF) is marketed as a potential alternative to acrylonitrile‐butyldiene‐styrene (ABS) and Polycarbonate/ABS for automotive interior components. PP‐PMF is more easily damaged by surface scratch/mar, thus limiting its acceptance for such applications. This study focuses on investigating the scratch/mar mechanisms of PP‐PMF having different mineral fillers and additives. A new method is introduced to characterize the scratch visibility by image analysis. A correlation is found between scratch visibility and scratch hardness measured by interferometer. It is found that Wollastonite filler imparts higher scratch/mar resistance. Addition of an interface modifier and a lubricant can further improve scratch/mar resistance. It is also found that Talc‐filled PP‐PMF has poor scratch/mar resistance, irrespective of the addition of an interface modifier or a lubricant.     

The effects of filler size on the properties of thermoplastic polyolefin blends

The effects of filler size on the properties of a thermoplastic polyolefin (TPO) blend were examined by using wollastonite and talc with particle sizes ranging from 1.2 to 40 μm. While addition of filler produced significant changes in the mechanical properties of the blend, filler size affected only impact strength. However, filler size, filler coating, and injection speed had a major effect on the surface properties of the blend. Faster injection produced denser “shear zone layers” which exhibited better scratch resistance and poorer paint adhesion than those obtained with slower injection. Scartch resistance and paint adhesion also decreased with increasing filler particle size. Filler coatings altered the scratch and adhesion properties of the polypropylene (PP) blends.     

Roles of additives in scratch resistance of high crystallinity polypropylene copolymers

Scratch behavior in neat and talc‐filled high crystallinity polypropylene (PP) copolymers containing various additives is investigated using a cosntant load scratch test and two types of indentation tests (Rockwell and Shore D). The talcfilled PP copolymer exhibits high scratch visibilityand scratch depth. The addition of a nucleating agent or lubricant improves the scratch resistance of the talc‐filled PP copolymer. Differential scanning calorimetry, scanning electron microscopy and attenuated total reflectance Fourier transform infrared spectroscopy are used to characterize crystallinity morphology and scratch mechanisms in PP systems. It is found that the scratch resistance of the PP copolymer systems investigated, in terms of scratch depth and scratch visibility, depends mainly on the fracture features generated during the scratch process. The influences of talc, nucleating agent and lubricant on the scratch behavior of PP are discussed.     

Experimental and numerical investigations of evaluation criteria and material parameters' coupling effect on polypropylene scratch

Nine PP systems were synthesized to investigate the coupling effect of elastic modulus and yield strength on its scratch behavior. Adopting an integrated approach of scratch test and finite element simulation, the tangential force, the residual scratch depth and the groove shoulder area are identified as the evaluation criteria of the scratch resistance of PP. With those identified criteria, the coupling effect of elastic modulus and yield strength on PP scratch is revealed that the PP with large yield strength and small elastic modulus owns a remarkable scratch resistance. The implication of the present work on designing the PP with good scratch resistant is also discussed. POLYM. ENG. SCI., 58:118–122, 2018. © 2017 Society of Plastics Engineers     

PP复合材料耐刮擦性能的研究

通过多指刮擦试验机对聚丙烯(PP)及其复合材料进行了系统的刮擦实验测试,采用光学显微镜观察了材料的刮擦损伤形貌,以研究PP及其复合材料的耐刮擦性能及损伤机理;通过差示扫描量热仪(DSC)测试了材料的结晶度,研究了耐刮擦助剂和磷酸盐成核剂对材料力学性能、结晶性能和耐刮擦性能的影响,以探讨材料力学性能、结晶性能与耐刮擦性能之间的关系。     

Effect of long-chain branching molar fraction on scratch behavior of polypropylene

Polymers containing a certain amount of long-chain-branching (LCB) structure are expected to possess improved mechanical properties over those of the linear structure counterpart. However, fundamental knowledge on the structure–property relationship in LCB containing polypropylene (PP) is still illusive. In the present study, a set of model PP systems containing an increasing molar fraction of LCB (5–19 mol%) were prepared by reactive extrusion to determine how LCB content may influence the scratch behavior of PP. It is shown that with only 5 mol% of LCB content in PP can improve resistance against scratch-induced fish-scale formation by over 25%. The improvement of scratch resistance is attributed to the increases in entanglement density in LCB-containing PPs, which is evidenced by their creep-recovery behavior. The present study demonstrates that the incorporation of LCB in PP leads to higher viscoelastic recovery and increased tensile strength, which account for the observed improvement in scratch performance. The usefulness of LCB in polymers for improving scratch performance is discussed.     

Relating scratch resistance to injection molding‐induced morphology of polypropylene

The relationship between the scratch resistance and the injection molding‐induced morphology of polypropylene (PP) was investigated. The crystal structure near the surface was controlled by the mold temperature and the doping of a nucleating agent (NA). Although α‐ and β‐NA were used to improve the scratch resistance of PP that was molded at a mold temperature of 40°C, both of the NAs only slightly affected the scratch resistance due to low crystallinity at the surface. When the mold temperature was increased, the skin layer became thin and a β‐form crystal formed. Plastic deformation under the scratch was limited in the frozen layer. Consequently, the thickness of the frozen layer (which had low crystallinity) had the predominant effect on the scratch resistance in comparison to the polymorphism differences. The crystal morphology was analyzed with synchrotron micro‐beam wide angle X‐ray diffraction and Fourier transform infrared spectroscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Scratch and mar resistance of filled polypropylene materials

Pigmented mineral-filled polypropylene (PP-PMF) is marketed as a potential alternative to ABS (acrylonitrile-butyldiene-styrene) for interior automotive components. However, PP-PMF is easily damaged by surface scratch and mar, thus limiting its acceptance for interior applications. This study investigates the test methods used to quantify the extent of scratch and mar damage and the effect of different mineral fillers on the scratch and mar resistance of PP-PMF. Correlation was found between scratch visibility and scratch hardness, which can be measured by laser profilometer. The PP-PMF specimen with 13 wt% talc is the worst in terms of scratch visibility. Wollastonite filler provided higher scratch and mar resistance, while the addition of 0.5 wt% lubricant showed some beneficial effect.