纳米TiO_2对聚丙烯/尼龙6共混物的增容作用

用SiO2和环氧基硅烷偶联剂对纳米TiO2进行修饰合成功能化纳米TiO2(sTiO2-O),然后与聚丙烯/尼龙6共混物进行熔融共混制备了sTiO2-O/PP/PA6纳米复合材料。通过拉伸、冲击等力学性能测试并结合扫描电镜对分散相尼龙6尺寸大小观察表明,由于功能化纳米粒子表面环氧基与PA6中氨基能发生化学反应,有效提高了两相的界面作用;少量纳米TiO2的加入使分散相尼龙6尺寸大幅度减小,并使复合材料拉伸和冲击强度大幅度提高,由此表明功能化纳米TiO2对不相容PP/PA6共混物具有良好的增容作用。     

多级拉伸PP/(PA1010+CB)复合材料的相形态演变

利用自主设计的多级拉伸挤出设备,制备了聚丙烯/(聚酰胺+炭黑)(PP/(PA1010+CB))复合材料,该聚合物熔体在挤出过程中受纵向拉伸力(F∥)和横向拉伸力(F⊥)的双向拉伸作用。通过扫描电子显微镜观察,随着分散相(PA1010+CB)含量的增加,CB在PA1010中含量的增加,相容剂含量的降低,分散相(PA1010+CB)的尺寸变大且变形能力增强,此时F⊥发挥作用,使分散相发生横向变形。体系中尺寸较大的分散相形成二维片状,尺寸较小的分散相形成纤维状。     

石墨烯/环氧树脂复合材料的制备及力学性能

分别通过超声共混法和原位还原法制备了石墨烯/环氧树脂复合材料。利用X射线光电子能谱(XPS)、X射线衍射(XRD)、光学显微镜和扫描电子显微镜(SEM)对复合材料的结构进行了表征,并对其力学性能进行了测试。结果表明,原位还原法制备的石墨烯/环氧树脂复合材料中,氧化石墨烯已经被成功地还原为石墨烯,并且石墨烯具有良好的分散性。力学性能测试结果表明,两种方法制备的复合材料的力学强度较纯环氧树脂明显提高。当石墨烯的量为m(GO)/m(EP)=0.3/100时,超声混合法制备的石墨烯/环氧树脂复合材料的拉伸强度和弯曲强度分别最大提高约29.2%和1.4%;而原位还原法制备的石墨烯/环氧树脂复合材料的拉伸强度和弯曲强度分别最大提高约40.5%和9.4%。     

聚酰胺6/氧化石墨烯复合材料的制备及其性能

为研究氧化石墨烯对聚酰胺6的相容性和力学性能的影响,以天然鳞片石墨为原料,采用改良的Hummers方法制备氧化石墨烯,用氯化亚砜将其活化得到酰氯修饰氧化石墨烯,再与氨气反应制备氨基化氧化石墨烯,采用原位聚合法制备出聚酰胺6/氧化石墨烯复合材料,利用扫描电子显微镜对其进行表征分析,通过在甲酸中的分散实验研究该材料的相容性,并利用拉伸实验测试其力学性能.结果表明:聚酰胺6成功以化学键形式键接到氨基化氧化石墨烯表面;氧化石墨烯在聚酰胺6基体中呈现均匀稳定分散;氧化石墨烯均匀分散于甲酸中,其在甲酸中的相容性得到了明显改善;氨基化氧化石墨烯质量分数为0.1%时,聚酰胺6/氧化石墨烯的拉伸强度和杨氏模量分别达到133和736 MPa.     

NBR-g-(GMA-co-St)的制备及其对PBT/PP复合材料的性能影响

以丁腈橡胶接枝甲基丙烯酸缩水甘油酯-苯乙烯共聚物[NBR-g-(GMA-co-St)]为相容剂，制备了聚对苯二甲酸丁二醇酯/聚丙烯(PBT/PP)复合材料。通过傅利叶红外光谱仪(FT-IR)对丁腈橡胶接枝物进行结构分析，通过力学、动态力学分析(DMA)、差示扫描量热仪(DSC)、热失重(TG)和扫描电子显微镜(SEM)等分析手段对复合材料进行表征。结果表明：接枝过程中加入与甲基丙烯酸缩水甘油酯(GMA)同质量比的苯乙烯能有效地提高相对接枝度，降低交联度；NBR-g-(GMA-co-St)具有增韧作用，添加NBR-g-(GMA-co-St)使PBT/PP复合材料的冲击强度上升，拉伸强度下降；NBR-g-(GMA-co-St)的加入使分散相粒子尺寸变小，改善了复合材料的相容性；相容剂的加入降低了复合材料的熔融温度和结晶温度。     

功能化纳米石墨烯片/PP-PP-g-MAH复合材料的制备与表征

采用溶液共混法制备了乙二胺功能化石墨烯片/聚丙烯-马来酸酐接枝聚丙烯(GS-EDA/PP-PP-gMAH)复合材料。利用FTIR、XRD、DSC、SEM和拉伸等表征手段对氧化石墨(GO)、GS-EDA及复合材料的结构和性能进行表征。研究结果表明:乙二胺(EDA)成功接枝到石墨烯片(GS)的表面上;在共混过程中,GS-EDA与PP-g-MAH之间产生了强烈的氢键作用,使GS-EDA均匀分散于基体中。DSC测试表明:GS-EDA的加入使GS-EDA/PP-PP-g-MAH复合材料的结晶峰向高温方向移动。随着GS-EDA加入量的增大,GS-EDA/PP-PP-gMAH复合材料的拉伸强度呈先升后降的趋势。当加入质量分数为0.5%的GS-EDA时,复合材料的拉伸强度达到最大,较纯PP-PP-g-MAH的增加了24.7%,较PP的增加了17.5%。SEM观察表明:加入少量的GS-EDA时,GS-EDA能均匀分散于基体中,但加入过多的GS-EDA将引起团聚。     

PP/ PA6原位成纤复合材料I. 形态与力学性能

不相容的通用热塑性塑料聚丙烯(PP) 和尼龙6 (PA 6) 共熔挤出, 当PA 6为分散相时, 得到了PA 6纤维分散于PP 基体中的原位复合材料。在PP 和PA 6的熔点之间成型, 可以保持住纤维的形态。材料的拉伸强度下降, 但冲击强度得到大幅度提高。     

阻燃型PA6／PP／硅灰石复合材料的制备及阻燃机理研究

采用固相力化学方法制备的聚丙烯接枝羟甲基丙烯酰胺作增容剂，以高效低毒的三聚氰胺三聚氰酸盐（MCA）作阻燃剂制备了阻燃型硅灰石填充尼龙6/聚丙烯复合材料，该复合材料具有很好的力学和阻燃性能，当MCA与聚合物质量比为10%时，该复合材料的极限氧指数达到31，拉抻强度为54.1MPa，悬臂梁缺口冲击强度为59.7J/m。通过TG和FT-IR分析对阻燃机理作了初步的探讨。     

氧化石墨烯/尼龙6复合材料的等温结晶行为

采用液相共混法制备氧化石墨烯(GO)/尼龙6(PA6)复合材料,利用差示扫描量热(DSC)和偏光显微镜(POM)表征该体系的等温结晶行为。结果表明,Avrami方程可较好地描述PA6和GO/PA6复合材料的等温结晶行为,氧化石墨烯对尼龙6起到成核剂作用,使其结晶速率增大,结晶活化能减少。等温结晶温度升高,PA6和GO/PA6的绝对结晶度和结晶速率减少。偏光显微镜观察证实,添加氧化石墨烯后的尼龙球晶细化。     

纳米粒子的分散状态对聚丙烯结晶行为的影响

用普通熔融共混与低剪切应力场下聚合物/纳米粒子的分散共混方法制备出聚丙烯/无机纳米粒子复合材料,采用示差扫描量热法(DSC)与偏光显微镜(PFM)对试样的结晶行为进行研究发现:在填充粒子含量相同情况下,均匀分散的纳米粒子可以较大提高聚丙烯的结晶温度,结晶速率,使晶体尺寸减小,而普通熔融共混制备的试样中,纳米粒子虽然也一定程度增加了聚合物的结晶温度,却并不改变晶体的尺寸。结果表明,当制备聚合物/纳米粒子复合材料时,纳米粒子在基体中的分散程度极大地影响聚合物基体的结晶行为。     

Compatibilizing effect of maleated polypropylene on the mechanical properties of injection molded polypropylene/polyamide 6/functionalized-TiO2 nanocomposites

TiO₂ nanoparticles were pretreated with excessive toluene-2,4-diisocyanate to synthesize TDI-functionalized TiO₂ (TiO₂-NCO), and then the polypropylene/polyamide 6/(PP/PA6, 70/30 wt%) blends containing 3 phr of the TDI-functionalized TiO₂ were prepared using twin-screw extruder followed by injection molding. Maleated polypropylene (PP-g-MAH) was used to compatibilize the blends. The mechanical properties of PP/PA6 blends based nanocomposites were studied through tensile and flexural tests. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to assess the fracture surface morphology and the dispersion of the TDI-functionalized TiO₂, respectively. The dynamic mechanical properties of PP/PA6 based nanocomposites were analyzed by using dynamic mechanical thermal analyzer (DMTA). The strength and stiffness of the PP/PA6 compounds were improved significantly in the presence of PP-g-MAH. This has been attributed to the synergistic effect of TDI-functionalized TiO₂ and PP-g-MAH. The PP-g-MAH compatibilized PP/PA6 compounds showed a homogeneous morphology supporting the compatibility improvement between PP, PA6 and TDI-functionalized TiO₂. TEM results revealed that the TDI-functionalized TiO₂ nanoparticles were exfoliated and uniformly dispersed in blends matrix. Possible chemical interactions between PP, PA6, TDI-functionalized TiO₂ and PP-g-MAH were proposed based on the experimental work.     

The falling weight impact properties of maleic anhydride compatibilized polypropylene–polyamide blends

A series of polypropylene–polyamide 6 (PP–PA) blends of composition 80: 20, 50:50 and 20:80 have been prepared in a twin screw extruder followed by injection moulding. Maleic anhydride grafted polypropylene was used as a compatibilizer for these blends. Static mechanical and falling weight impact tests were performed on these blends. The fracture surfaces of impact specimens were subsequently examined by scanning electron microscopy (SEM). The mechanical properties of the blends were found to be strongly dependent on the PP–PA blend ratios. The Young’s modulus, tensile strength and impact energy were observed to increase with increasing PA content. The impact strength was better in blends when the PA content approached 80 wt %. SEM observations revealed that the addition of compatibilizer resulted in good adhesion between the PP dispersed domains and PA matrix in the PP–PA 20:80 blend. Furthermore, the SEM fractographs also indicated that the cold drawn of PA matrix and debonding of PP domains were responsible for the high impact strength of this blend. This revised version was published online in November 2006 with corrections to the Cover Date.     

RSMA增容PA6/PP共混物的形态结构与增容机理

采用ＲＳＭＡ为增容剂制备了ＰＡ６／ＰＰ共混物,研究了ＲＳＭＡ增容ＰＡ６／ＰＰ共混物的形态结构和热行为以及晶态结构,并探讨ＲＳＭＡ增容ＰＡ６／ＰＰ共混物的增容机理结果表明,ＰＡ６／ＰＰ共混物为热力不相容的海岛型两相结构,ＲＳＭＡ的加入改善ＢＰＡ６与ＰＰ相间的相容性,使两相分均匀,分散度提高。ＲＳＭＡ对ＰＡ／ＰＰ共混物的增容机理可用界面－分散相复合模型描述。     

Toughening of polyamide 6 with β-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–diene rubber grafted with maleic anhydride blends

The toughening of polyamide 6 (PA 6) with β-nucleated thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene–propylene–diene rubber grafted with maleic anhydride (EPDM-g-MAH) blends was studied. A series of TPVs without and with different dosage of β-nucleating agent (β-NA) were prepared and used to toughen PA 6 at the same proportion. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements showed that β crystals of PP were effectively induced in the TPVs. The PA 6 blends toughened with β-nucleated TPVs (β-TPVs) exhibit significantly enhanced toughness, balanced mechanical properties and thermal properties compared with PA 6 toughened by TPV without β-NA or only by EPDM-g-MAH. Phase morphologies of the blends characterized by scanning electron microscopy (SEM) showed that better interfacial adhesion caused by the migration of β-NA from PP to PA 6/PP interface and PP/EPDM-g-MAH interface gives rise to more uniform dispersion and smaller size of the dispersed phase; moreover, the core–shell structure comprised of rubber particles enveloped by PP on the surface, brings about easier and stronger interference of the stress field of EPDM phase.     

衣康酸接枝PP对PA6／PP共混物增容作用机理的研究

以马来酸酐接枝作对照，用ＥＳＣＡ，ＳＡＸＳ，ＷＡＸＤ，ＳＥＭ、力学性能测试等手段，研究了衣康到接枝对ＰＡ６／ＰＰ共混物和增容作用机理，证实共混物中有ＰＡ－ｃｏ－ｇＰＰ共聚物生成，讨论了ｇＰＰ，ＰＡ－ｃｏ－ｇＰＰ的结构与后者生成量和增容效率之间的关系，提出了ＰＡ－ｃｏ－ＭＰＰ和ＰＡ－ｃｏ－ＩＰＰ的增容作用模型。     

Effect of different polypropylenes and compatibilizers on the rheological,mechanical and morphological properties of nylon 6/PP blends

In this work, the rheological, mechanical and morphological properties of nylon 6/polypropylene compatibilized blends were investigated. Two types of polypropylene were used. One with MFI of 40 g/10 min (PP H103) and the other with MFI of 3.5 g/10 min (PP H503). The compatibilizers used were polypropylene grafted with 6% of acrylic acid (PPgAA) and polypropylene grafted with 1% of maleic anhydride (PPgMA). The blends composition was 80/20 (wt%) for the PA6/PP binary blends and 80/10/10(wt%) for the nylon 6/PPgAA/polypropylene and nylon 6/PPgMA/polypropylene ternary blends. Torque rheometry analysis showed that when PPgAA and PPgMA were added to nylon 6/polypropylene blends, there was an increase in the torque, indicating that reactive compatibilization has occurred. There is no influence of the polypropylene MFI on the mechanical properties of the uncompatibilized and compatibilized blends. The impact strength of the blends containing PPgMA were greater than those of the blends containing PPgAA. The blends containing PPgAA are unstable. SEM analysis showed that PPgMA improves considerably the adhesion between PA6/PP phases, leading to good mechanical properties.     

PP/PA1010共混物的形态结构及力学性能的研究

利用红外光谱、扫描电子显微镜和力学测试等方法, 甲基丙烯酸环氧丙酯熔融接枝聚丙烯ＰＰ－ｇ－ＧＭＡ对不同组成的ＰＰ／ＰＡ１０１０共混物形态结构和力学性能的影响。     

Combined effect of the nature of the filler and the compatibilizer on the weld line properties of filled blends

The mutual effect of the nature of the filler and the compatibilizer on the properties of a ternary blend based on polypropylene (PP) polyamide-6 (PA) and an inorganic phase is investigated. Low aspect ratio irregular shaped CaCO₃ and high aspect ratio plate-like talc are selected as inorganic phases. The effect of different filler levels on the morphology of the weld line region and the region far from the weld line are studied while special attention is paid to both uncompatibilized and compatibilized PPPA blends with maleic anhydride grafted polypropylene (MA-g-PP). It is observed from scanning electron microscopy (SEM) studies that plate-like talc reduces the elongated domain size in the weld line region much more effectively than low aspect ratio CaCO₃ for uncompatibilized filled blends. Although both filler are selectively wetted by the dispersed PA phase, the morphology homogenization in the weld line region is found to be related to the ability of the filler to reduce the elongated domain size by increasing the viscosity of dispersed phase rather than the shape of the filler. The selective wetting of talc particles by the PA phase seems to be beneficial in increasing weld line strength by increasing the viscosity of the PA dispersed phase with respect to filler content much faster than CaCO₃. However, the additional compatibilization effect causes much finer, homogeneous spherical PA/ CaCO₃ domains dispersed within the PP matrix compared to plate-like PA/talc domains, which are highly oriented at the weld line. For that reason, the shape of the filler is of predominant importance to achieve homogeneous morphology in the weld line region. Compared to uncompatibilized filled blends, low aspect ratio irregular shaped CaCO₃ yields better weld line strength with respect to all filler levels. For compatibilized PPPA filled blends, the shape of the filler is of supreme significance in order to achieve better mechanical properties especially where weld line properties are concerned.     

力化学方法制备PP—g—HMA增容PA6／PP／硅灰石复合材料的形？…

以力化学方法制备的Ｎ－羟甲基丙烯酰胺接枝聚丙烯（ＰＰ－ｇ－ＨＭＡ）作尼龙６（ＰＡ６）／聚丙烯（ＰＰ）共混体系的增容剂,将增容尼龙６／聚丙烯共混体系与硅灰石复合。研究了复合材料的形态结构、硅灰石用量、偶联剂种类和用量以及增容剂等对复合材料的力学性能的影响。结果表明,ＰＰ－ｇ－ＨＭＡ能提高ＰＡ６／ＰＰ／硅灰石复合材料的力学性能,而ＫＨ－５５０和ＯＮ－３３０两种偶联剂复配使用则可以显著提高ＰＰ－ｇ－ＨＭ