ABS塑料化学镀铜的研究

以ABS塑料为基体,甲醛为还原剂,EDTA为络合剂,研究了化学镀铜的基本工艺。考察镀液的pH值、温度、时间对镀铜的影响,确定最佳工艺参数为pH=12.5、T=50℃、t=40min。通过扫描电镜和X射线衍射分析了最佳条件下镀铜层的形貌和成分,结果表明:该镀层外观红亮,表面平整,杂质含量很少。     

丙烯腈-丁二烯-苯乙烯塑料玩具中的双酚A在人体模拟液中的迁移规律

提出了丙烯腈-丁二烯-苯乙烯(ABS)塑料玩具中双酚A在人体模拟液中迁移规律的研究方法。用液相色谱-串联质谱仪对ABS塑料中双酚A在人体模拟液中的迁移量进行了测定,并与Fick扩散定律相结合,求算出了扩散系数D和分配系数KP/F,建立了ABS塑料中双酚A在37℃下经模拟唾液和模拟汗液的迁移模型。利用扩散系数D和分配系数KP/F可以在测出塑料中双酚A总量之后,直接计算出塑料在模拟液中双酚A的最大迁移时间和最大迁移量,达到省时、省力、省成本的效果。     

NiCF/ABS复合材料的制备及电磁屏蔽效能研究

探讨了碳纤维(CF)表面镍金属的化学镀工艺,制备了镀镍碳纤维(NiCF),采用密炼工艺制备了ABS基体复合材料,研究了CF和NiCF含量对复合材料的导电性能及电磁屏蔽效能的影响。结果表明:采用化学镀的方法在碳纤维表面镀覆了金属镍,所形成的镀层均匀致密;镀覆时间为5min时,镀镍后的碳纤维电阻率降低两个数量级;复合材料电阻率随CF、NiCF含量的增加而逐渐减小;复合材料电磁屏蔽效能随CF、NiCF含量的增加而逐渐增加,当NiCF含量为25%(wt)(约13.3vol%)时,电磁屏蔽效能最高可达51dB。     

气相色谱-质谱法测定塑料中四溴双酚A

提出了气相色谱-质谱法测定塑料中四溴双酚A含量的方法。样品经乙酸乙酯超声提取20min后,氮气吹干。用甲苯5.0mL溶解残渣,经乙酸酐衍生化后,所得衍生产物过DB-5MS色谱柱分离,电子轰击离子源质谱检测。四溴双酚A的质量浓度在0.1～100mg.L-1范围内与其峰面积呈线性关系。以ABS和PS塑料样品为基体,进行加标回收试验,回收率在分别为97.0%和94.2%,相对标准偏差(n=5)小于6.5%。     

丙烯腈-丁二烯-苯乙烯(ABS)塑料中残留单体的溶解沉淀-气相色谱法测定

建立了溶解沉淀-气相色谱同时测定丙烯腈-丁二烯-苯乙烯（ABS）塑料中9种有毒有害残留单体的分析方法。以N,N-二甲基甲酰胺为溶剂溶解ABS树脂,然后用甲醇作沉淀剂将高聚物进行沉淀,使残留单体与高聚物进行分离而继续留在溶液中,取溶液进行气相色谱分析。通过优化气相色谱的分离条件,实现了9种残留单体的成功分离,9种残留单体的平均回收率为91％～110％,测定结果的相对标准偏差为1．27％～3．16％,检出限（S／N=5）为0．936～1．639mg／kg。该方法比国家标准GB／T 5009．152-2003具有更广的适应性,应用此方法对4种牌号的ABS塑料中9种残留单体进行测定,获得满意的结果。     

微波消解-电感耦合等离子体原子发射光谱(ICP-AES)法测定ABS塑料中Pb、Cd、Hg

以ABS塑料为研究对象,采用微波消解法进行样品的前处理,使用电感耦合等离子体原子发射光谱(ICP-AES)法测定ABS塑料中Pb、Cd、Hg,结果表明,Pb、Cd、Hg加标回收率均在95.0%～105%,测定相对标准偏差(RSD)均小于3%,方法在缩短样品前处理时间的同时得到较高的元素消解回收率和较为理想的精密度,适用于ABS塑料中重金属含量的快速测定。     

成型方式对不同木塑复合体系的性能影响研究

以木粉为填充材料,以PE(聚乙烯)、PP(聚丙烯)为塑料基体,分别采用混炼-模压工艺和挤出-注塑工艺制备木塑复合材料,对比研究不同复合材料的力学性能、热性能以及流变性。结果表明,混炼-模压工艺制备的PE基复合材料综合性能较优,而挤出-注塑工艺制备的PP基复合材料综合性能较优,且在PE塑料系列中,HDPE(高密度聚乙烯)基复合材料综合力学性能最好,LLDPE(线性低密度聚乙烯)基复合材料的冲击韧性最好,但其综合力学性能较差。     

塑料产品中SAN及ABS相关测定标准发布

2009年2月1日,由兰州石化公司负责起草的《塑料苯乙烯-丙烯腈(SAN)模塑和挤出材料第2部分:试样制备和性能测定》(简称SAN标准)和《塑料苯乙烯-丙烯腈共聚物(ABS)残留丙烯腈单体含量的测定气相色谱法》(简称ABS标准)两项标准由国家标准委员会正式发布。新标准发布既规范了国内塑料产品分析检测流程,也为塑料产品质量升级提供数据保障。(仪器信息网)塑料产品中SAN及ABS相关测定标准发布     

新型含磷阻燃剂的合成及阻燃PC/ABS的热稳定性能

通过9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)、乙烯基甲基二甲氧基硅烷(WD-23)和γ-氨丙基甲基二乙氧基硅烷(DB902)之间的反应,合成了一种新型含磷阻燃剂:10-(乙基甲基二甲氧基硅烷)-9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物/γ-氨丙基甲基二乙氧基硅烷共聚物(DPWDF).利用热重分析(TGA)研究了阻燃剂及阻燃PC/ABS的热稳定性.结果表明:480 ℃以后,阻燃剂在空气氛围中的残炭量比在氮气氛围中的高;阻燃剂提前于基体PC/ABS分解,有利于促进基体成炭,提高基体的高温残炭量.     

NH4F对化学镀镍液的作用机理及镀层性能的影响

氟元素是周期表中最活泼的非金属元素,有着最强的电负性,氟化物有着特殊的化学性能。关于氟化物在化学镀镍磷工艺中的应用已有报道,在镁基体上化学镀的前处理过程中,常用氢氟酸或氟化氢铵来进行活化处理;硅片表面上的化学镀也通常用HF与HNO3或HCl的混酸来活化,使硅片表面产生Si-H键。另外,如果在化学镀液中添加少量的氟化钠,则起到加速的作用[1]。对于氟化物在化学镀镍磷工艺中的报道仅限于此,未见有关氟化物在化学镀中其它作用的研究。鉴于此,本工作以氟化铵为研究对象,对其在弱碱性的条件下对化学镀液的缓冲能力、沉积速度以及所得镀层性能的影响进行了研究。     

Influence of temperature on the surface property of ABS resin in KMnO4 etching solution

The KMnO₄-H₃PO₄-H₂SO₄ system was used to roughen and hydrophilically modify on the surface of ABS resin at different etching temperatures, and then, electroless nickel plating process was carried out. The surface of ABS resin after etching was characterized by XPS and SEM. It is found that the surface etching effect of ABS resin is relatively good when the etching temperature is 65°C. The resin surface generates ─OH and ─COOH hydrophilic groups, the roughness of resin surface is increased significantly, and the surface hydrophilic contact angle is 40.51°. After electroless nickel plating on the ABS etching surface, the bonding force of the coating can reach 2.73 MPa. Electrochemical polarization curves and electrochemical impedance spectra also show that the corrosion resistance of coating after 65°C etching postprocessing is improved.     

Adsorption and adhesion studies of PdSn‐nanoparticles on protonated amine and carboxylic acid‐terminated surfaces

Electroless plating of acrylonitrile‐butadiene‐styrene‐terpolymers (ABS‐plastics) is used for decorative applications and relies on the immobilization of catalytic palladium‐tin nanoparticles. We used chemical force microscopy to measure the adhesion force of palladium‐tin nanoparticles on a patterned amine and carboxyl‐terminated surface prepared by micro‐contact printing. The kinetics of the adsorption process and the population density of the nanoparticles on amine and carboxyl‐terminated surfaces were monitored by quartz crystal microbalance with dissipation analysis. The surface chemistry was investigated by means of polarization‐modulated infrared reflection absorption spectroscopy and X‐ray photoelectron spectroscopy. Enhanced adhesion and population density of PdSn nanoparticles on protonated amine‐terminated surfaces compared with carboxyl‐terminated surfaces is observed. Copyright © 2016 John Wiley & Sons, Ltd.     

Dynamics of the interface in a model composite system

A review of recent experiments from the authors laboratory on the dynamics of aminofunctional silane coupling agents is given. Of special emphasis are two coupling agents, aminopropylsilane (APS) and aminobutylsilane (ABS) which were deuterated in the γ-position. These two coupling agents have similar chemical behavior, but different dynamics. Deuterium NMR studies reveal that the APS moves slower on the silica surface than ABS. The mobility of the interfacial ABS was also found to be significantly slowed when it was overcoated with a polymerized layer of bismaleimide to form a composite. When the composite was treated with water, the interfacial mobility of the ABS increased. The flexural strength of the APS treated composite was the highest compared to ABS-treated and bulk glass in an epoxy-glass composite.     

Mechanism study on char formation of zinc acetylacetonate on ABS resin

The mechanism of char formation effect of zinc acetylacetonate(Zn(acac)2) on acrylonitrile-butadiene-styrene copolymer(ABS) was studied. Thermal gravimetric analysis(TGA) was used to study the mass loss and char yield of ABS composites. In situ temperature-dependent Fourier transform infrared spectroscopy(FTIR) was used to characterize the chemical change during thermal decomposition. Roman spectroscopy and scanning electron microscopy(SEM) were applied to characterize the structure and morphology of the char after combustion. Results showed that the presence of Zn(acac)2 not only slowed down thermal decomposition of the ABS composites, but also increased the charred residue. A more compact and denser char layer with higher graphitization degree was formed for ABS composites with Zn(acac)2. To study the char formation mechanism of Zn(acac)2 on ABS, thermal decomposition was analyzed for the composites of Zn(acac)2 with PB, PS and SAN, respectively. Also, the chemical structure change was investigated for Zn(acac)2 during thermal decomposition. Based on these results, it was deduced that the increase of char yield of ABS composites was probably attributed to the interaction between the units of acrylonitrile in ABS and zinc acetate, produced during the thermal decomposition of Zn(acac)2. A proposed mechanism for crosslinking and the subsequent char formation was presented.     

Chemical and structural changes at the ABS polymer-copper metal interface

Creating oxygen containing moieties (hydroxyl or carbonyl) on polymer substrate surfaces is known to increase the adhesion strength of polymers to metals. However, we noticed adhesion increase with time even though no pre- or post-treatment of the polymer substrate was done. In the case of sputtered and galvanically strengthened copper coatings on acrylonitrile-butadiene-styrene polymer (ABS) substrate, the adhesion strength increased from approximately 6 J/m² to 53 J/m² during a 1008-h period. During this period structural and chemical changes of the polymer near the interface take place. Carbonyl functionalities developed on the ABS surface are most likely responsible for the large increase in the adhesion strength. Chemical changes of the polymer are probably a consequence of the galvanic deposition and a close contact of ABS with copper which is known to facilitate the oxidation of ABS.     

Clarification and discussion of chemical transformations involved in thermal and photo-oxidative degradation of ABS

The mechanisms of thermal and photo-oxidative degradation of unstabilized samples of ABS have been discussed in terms of the known chemistry of the unsaturated isomeric units of PB and the chemical species identified by either i.r. spectroscopy or chemical studies. The reactions which lead to the loss of unsaturation and loss of elastomeric properties of the rubber segment, production of hydroxyl and carbonyl species and the development of cross-linking and colour are extremely complex. High degree of correlation between the outlined chemical transformations and the identifiable reaction products has led to a more definitive and clearer mechanism of degradation of ABS, and by inference, PB and PB-based polyblends.     

化学镀镍磷镀层及其耐蚀性研究

针对工业实际对提高防护层防腐、耐磨性能的要求,对化学镀镍磷镀层的方法,镀敷液配方等进行了分析,对其腐蚀率进行了测定,并对镀层性能进行了表征;讨论了影响腐蚀率的若干重要因素;对有关工艺进行了优化,从而在多种基质上获得了抗腐蚀性较好的镍磷镀层,初步研究证明,其性能优于电镀方法所获得的镀层.     

Automatically generated Coulomb fitting basis sets: design and accuracy for systems containing H to Kr

For intermediate sized chemical systems the use of an auxiliary basis set (ABS) to fit the charge density provides a useful means of accelerating the performance of various quantum chemical methods. As a consequence much effort has been devoted to the design of various ABSs. This paper explores a fundamentally new approach where the ABS is created dynamically based on the specific orbital basis set (OBS) being used. The new approach includes a parameter that is used to coalesce candidate fitting functions together but which can also be used to provide some coarse grain control over the number of functions in the ABS. The accuracy of the new automatically generated ABS (auto-ABS) is systemically studied for a variety of small systems containing the elements H-Kr. Errors in the Coulomb energy computed using auto-ABS and with a variety of OBSs are shown to be small compared to errors in the Hartree-Fock energy due to incompleteness in the OBS. In contrast to fixed size ABSs, the use of auto-ABS is shown to lead to smaller errors as the size (quality) of the OBS is expanded. The performance of auto-ABS is also compared with the use of the recently proposed universal fitting sets [Weigend, Phys. Chem. Chem. Phys. 8, 1057 (2006)] for 180 compounds containing atoms from H to Kr.     

Effect of dissolution-based recycling on the degradation and the mechanical properties of acrylonitrile-butadiene-styrene copolymer

A dissolution-based recycling technique for acrylonitrile-butadiene-styrene copolymer (ABS) is proposed, and the effects of repeated recycling cycles are studied measuring changes in chemical structure, melt viscosity, and tensile and impact properties. Acetone as solvent, 0.25 g/ml concentration, room temperature and 40 min for dissolution have been found to be the most reliable recycling parameters. FTIR, DSC and MFI results have shown that the dissolution-based recycling itself does not degrade the ABS. However, TGA analysis suggests that during the dissolution some stabilizers are probably eliminated, and consequently degradation takes place in the following injection moulding step. Darkening of recycled ABS is attributed to the butadiene degradation, pointed out by FTIR results. Otherwise, the chemical structure of the SAN matrix has not been modified, but its molecular weight has been reduced. The modulus of elasticity is not affected even after four recycling cycles. However, yield stress and impact strength decrease after the first recycling cycle, and remain constant in the following steps.     

Activity‐Based Sensing: A Synthetic Methods Approach for Selective Molecular Imaging and Beyond

Emerging from the origins of supramolecular chemistry and the development of selective chemical receptors that rely on lock‐and‐key binding, activity‐based sensing (ABS)—which utilizes molecular reactivity rather than molecular recognition for analyte detection—has rapidly grown into a distinct field to investigate the production and regulation of chemical species that mediate biological signaling and stress pathways, particularly metal ions and small molecules. Chemical reactions exploit the diverse chemical reactivity of biological species to enable the development of selective and sensitive synthetic methods to decipher their contributions within complex living environments. The broad utility of this reaction‐driven approach facilitates application to imaging platforms ranging from fluorescence, luminescence, photoacoustic, magnetic resonance, and positron emission tomography modalities. ABS methods are also being expanded to other fields, such as drug and materials discovery.