改性载银磷酸锆及其抗菌聚乙烯薄膜的研究

以硬脂酸单甘油酯、油酸酰胺、稀土／铝酸酯为改性剂,分别对载银磷酸锆进行表面改性,用吸水性测定法、粘度法分析载银磷酸锆的改性效果,用扫描电镜观察载银磷酸锆在聚乙烯基材中的分散均匀性。检测了含载银磷酸锆的聚乙烯薄膜的力学性能和抗菌性能。结果表明：采用油酸酰胺改性的载银磷酸锆。其疏水性和分散均匀性好;含1％载银磷酸锆（经油酸酰胺改性）的聚乙烯薄膜,拉伸强度（纵／横向）为23．14／14．25MPa,断裂伸长率（纵,横向）为147．9％／310．6％,直角撕裂强度（纵,横向）为134.31／87．50kN／m,抗菌率达99％以上。     

聚乳酸/纳米载银磷酸锆熔纺纤维制备及性能

利用双螺杆挤出机将聚乳酸(PLA)切片和纳米载银磷酸锆颗粒共混制备纳米载银磷酸锆质量分数为20%的PLA母粒。将母粒和纯PLA切片按照不同比例共混熔纺制备PLA/纳米载银磷酸锆共混纤维。研究了共混纤维的制备方法,运用扫描电子显微镜观察了纤维束外部形貌,测试了纤维的力学及抗菌性能。结果表明,纳米载银磷酸锆在纤维中有少量凝聚,总体分散均匀;随着纳米载银磷酸含量提升,纤维断裂强度先增大后降低,同时纤维的抗菌性不断增加。当载银磷酸锆含量达到1.5%时,纤维的断裂强度最大为0.85 c N/dtex,对大肠杆菌和金黄色葡萄球菌抑菌率达99.9%。     

磷酸锆化合物合成研究进展

磷酸锆类化合物是近年发展的一类新型多功能材料,在催化领域有广泛应用。本文概述磷酸锆类化合物的合成方法及过程,综述近年来层状磷酸锆和具有分子筛结构的多孔磷酸锆的合成进展,并展望了磷酸锆化合物合成的方向。     

Oxidative coupling of methane over sodium-chloride-added sodium zirconium phosphates

Monosodium zirconium phosphate or disodium zirconium phosphate by itself did not catalyze the oxidative coupling of methane and also the deep oxidation of methane. However, NaCl-added sodium zirconium phosphates showed markedly increased activity and high C₂₊ selectivity in the oxidative coupling of methane, which indicates that chlorine species or NaCl plays an essential role in the catalytic action. The catalytic performance became more stable with increasing content of NaCl. The primary reason for the catalyst deactivation is the loss of chlorine, and a possible secondary reason is the transformation of catalytic substance to the sodium zirconium phosphates having higher Na/Zr ratios or decomposition of sodium zirconium phosphates to zirconium oxide and sodium phosphate. Two kinds of surface chlorine species were observed, and the lower-binding-energy species is considered to be much more active than the higher-binding-energy species in methane activation, although the latter is present in a larger amount than the former.     

无定形介孔磷酸锆固定葡萄糖氧化酶的直接电化学

利用无定形介孔磷酸锆(ZrP)为载体,通过吸附法固定葡萄糖氧化酶(GOD),修饰玻碳(GC)电极得到GOD/ZrP/GC电极。在0.1 mol·L^-1磷酸盐缓冲溶液中,利用循环伏安法研究了GOD/ZrP/GC电极的直接电化学行为和对葡萄糖的催化性能。结果表明,无定形磷酸锆ZrP为载体修饰的电极GOD/ZrP/GC其电化学反应电子转移速率快、表观覆盖量大;对葡萄糖的检测表现出较快的电流响应和较高的灵敏度,说明无定形磷酸锆更有利于GOD的固定和酶电极的直接电化学。     

含载银磷酸锆的抗菌EVA发泡材料的研究

以乙烯-乙酸乙烯酯共聚物(EVA)为原料,载银磷酸锆为抗菌剂,制备抗菌EVA发泡材料。采用硅烷、硼酸酯、铝酸酯3种偶联剂,分别对载银磷酸锆粉体表面改性。结果表明:采用硼酸酯改性的载银磷酸锆粉体,疏水性和分散性效果最好;含质量分数为1%的载银磷酸锆(经2.5%硼酸酯处理)的EVA发泡材料,其泡孔孔径增大,相对密度115 kg/m~3,拉伸强度2.02 MP,撕裂强度4.60 kN/m,断裂伸长率248%,对大肠杆菌和金黄色葡萄球菌的抗菌率分别达到99.9%和97.8%,物理力学性能和抗菌性能优良。     

油酸酰胺改性载银磷酸锆/聚乙烯抗菌薄膜的研究

以油酸酰胺为改性剂,载银磷酸锆为抗菌剂,线型低密度聚乙烯为载体树脂,制备了抗菌母粒和抗菌聚乙烯薄膜。用吸水性测定法、红外光谱法分析载银磷酸锆的改性效果,用扫描电镜观察载银磷酸锆在聚乙烯基材中的分散情况,检测了薄膜的力学性能、透光率、透气量、抗菌率。结果表明:经油酸酰胺改性的载银磷酸锆疏水性好,在基体中分散均匀;当抗菌母粒含量为5%时,聚乙烯薄膜的纵向拉伸强度和横向直角撕裂强度略有下降,断裂伸长率、横向拉伸强度、纵向直角撕裂强度均有不同程度的提高,透光率下降3.4%,透气量提高30.18%,抗菌率达99%以上。     

莫来石-磷酸锆复相陶瓷材料性能的研究

本文研究了在莫来石中添加低膨胀第二相磷酸锫的莫来石-磷酸锆复相陶瓷的性能,找到了在保证强度的同时,获得较低热膨胀系数的莫来石-磷酸锆复相陶瓷的制备方法.实验表明：莫来石-磷酸锆复相陶瓷能通过将莫来石粉料与磷酸锆粉料或莫来石粉料与磷酸锆生料粉按不同质量比混合烧结制备;加入1wt％的MgO作为烧结助剂,在1350℃烧成的样品具有最低的热膨胀系数和较小的吸水率.     

银系磷酸锆抗菌剂晶体结构与抗菌剂制备及性能关系初探

银系磷酸锆抗菌剂就结构分为层状磷酸锆抗菌剂和立方体磷酸锆抗菌剂。两者在制备方法,抗变色性,银离子析出率及抗菌时间等多方面抗菌剂性能有所不同。本文试着从两者的晶体结构角度出发,探究两者性能差异的原因。     

有序介孔磷酸锆的研究进展

简要阐述了磷酸锆材料的特点和应用发展现状,重点探索了有序介孔磷酸锆的制备方法及表征技术,对于磷酸锆材料研究及制备中存在的问题进行了归纳。     

Development of Zirconium/Magnesium Phosphate Composites for Immobilization of Fission Products

Novel chemically bonded phosphate ceramics have been investigated for the capture and stabilization of volatile fission-product radionuclides. We have used low-temperature processing to fabricate zirconium phosphate and zirconium/magnesium phosphate composites. A zirconium/magnesium phosphate composite has been developed and shown to stabilize ash waste that has been contaminated with a radioactive surrogate of the ¹³⁷Cs and ⁹⁰Sr species. Excellent retention of cesium in the phosphate matrix system was observed in both short- and long-term leaching tests. The retention factor determined by the USEPA Toxicity Characteristic Leaching Procedure was one order of magnitude better for cesium than for strontium. The effective diffusivity, at room temperature, for cesium and strontium in the waste forms was estimated to be as low as 2.4 × 10⁻¹³ and 1.2 ×10⁻¹¹ cm²/s, respectively. This behavior was attributed to the capture of cesium in the layered zirconium phosphate structure via an intercalation ion-exchange reaction, followed by microencapsulation. However, strontium is believed to be precipitated out in its phosphate form and subsequently microencapsulated in the phosphate ceramic. The performance of these final waste forms, as indicated by the compression strength and the durability in aqueous environments, satisfies the regulatory criteria.     

Study of Catalyst Selectivity in the Oxidation of Phenol

The selectivity of -crystalline zirconium phosphate, amorphous zirconium phenylphosphonate, amorphous zirconium molybdenum phosphate and microporous crystalline aluminium methylphosphonate was evaluated in oxidation reactions of phenol. The different selectivities are correlated to the properties and structure of each compound.     

Effects of barium zirconium titanate on the properties of β-tricalcium phosphate bioceramics

In the present work, a new composite between β-tricalcium phosphate (a bioceramic material) and barium zirconium titanate (a ferroelectric material) were fabricated. Beta-tricalcium phosphate (β-TCP) powder was synthesized from egg shells while barium zirconium titanate powder was synthesized from metal oxide powders. The composites were fabricated by a solid-state reaction method. Effects of barium zirconium titanate on many properties of the composites were investigated. Barium zirconium titanate additive improves the electrical properties of the composites such as dielectric, ferroelectric and piezoelectric properties. Furthermore, the mechanical properties, such as hardness are improved by the additive. In-vitro bioactivity test suggests that β-tricalcium phosphate has a higher apatite forming ability as compared to the BZT. The obtained results indicate that the composites are a promising biomaterial candidate.     

含CeO_2掺杂载银磷酸锆的抗菌EVA发泡材料研究

以乙酸-乙酸乙烯共聚物(EVA)为原料,氧化铈(CeO2)掺杂复合载银磷酸锆为抗菌剂,制备抗菌EVA发泡材料。利用无转子硫化仪、扫描电镜等分析了CeO2掺杂复合载银磷酸锆对EVA发泡材料发泡压力和泡孔形态的影响,同时检测了抗菌EVA发泡材料的力学性能及抗菌率。结果表明:含2.8%CeO2掺杂复合载银磷酸锆的EVA发泡材料,其模压发泡过程的发泡压力增大,发泡倍率增加,泡孔孔径增大,相对密度降低,物理力学性能优于普通EVA发泡材料,对大肠杆菌和金黄色葡萄球菌的抗菌率分别为99.10%和98.85%,在自来水中浸泡30天后,其抗菌率仍分别达到98.83%和98.54%。     

SYNTHESIS, CHARACTERIZATION AND APPLICATION IN PEMFC OF ZIRCONIUM OXO PHOSPHATE-SULFATE

Mesoporous zirconium oxo phosphate-sulfate was synthesized by hydrothermal method with hexadecyltrithylammonium bromide(CTAB)as the template and with zirconium nitrate or zirconium oxychloride as zirconium source.The optimum two-stage process was established, ~(31)P MAS NMR showed that the states of phosphate species were changed with further postsynthesis treatment by sulfate acid. The transformations of the structures at different temperatures from room temperature to 1173 K were investigated by XRD. The mesoporous structure could be retained up to 723 K. The proportion of tetragonal phase (T-ZrO_2) to monoclinic phase (M-ZrO_2) decreased with increasing temperature from 923 K to 1173 K. After the as-synthesized sample was treated by H_3PO_4 and H_2SO_4, T-ZrO_2 kept predominant at wide temperature range. The performance of proton exchange membrane fuel cell (PEMFC) with the recast composite membrane of Nafion and zirconium oxo phosphonate-sulfurate has been investigated.     

A blue-violet zirconium silicate pigment with admixtures of condensed cobalt phosphates

The zirconium silicate described represents a pigment of a new hue and is suitable for ceramics. Its colour is due to particles of condensed cobalt phosphates incorporated as the so-called inclusions in zirconium silicate microcrystals. A combination of disodium hexafluorosilicate and lithium hydroxide with cryolite has been used as the mineralizer in the pigment synthesis. The chromophore is cobalt dihydrogen phosphate or the corresponding mixture of cohalt(II) oxide and phosphoric acid, which are calcined to give intensely coloured particles of the condensed cobalt phosphate. The effects of the chromophore and of the individual components of the mineralizer on the colour hue of the pigment have been evaluated and their optimum amount in the starting mixture estimated. The calcination temperatures found and the yields of products correspond to other zirconium silicate pigments. The consumption of expensive cobalt is very low, and the pigment is applicable to all kinds of ceramic glazes.     

Propylene polymerisations with novel heterogeneous combination metallocene catalyst systems

Propylene was polymerised with novel combination metallocene catalyst systems prepared by an emulsion-based heterogenisation method in liquid monomer conditions. The catalyst combinations investigated were rac-dimethylsilanylbis(2-methyl-4-phenyl-1-indenyl)zirconium dichloride/rac-[ethylenebis(2-(tert-butyldimethylsiloxy)indenyl)]zirconium dichloride/methylaluminoxane (MAO) (1 + 2) and rac-dimethylsilanylbis(2-methyl-4-phenyl-1-indenyl)zirconium dichloride/rac-dimethylsilanylbis(2-isopropyl-4-[3,5-dimethylphenyl]indenyl)zirconium dichloride/MAO (1 + 3). The effects of polymerisation temperature and hydrogen on catalyst performance and polymer properties, as well as copolymerisation with hexene and ethylene were investigated. Depending on the polymerisation conditions, M_w of polypropylene varied from 144 to 286 kg/mol for 1 + 2 and from 200 to 390 kg/mol for 1 + 3. Combination 1 + 2 produced broader molecular weight distribution (MWD) than 1 + 3, and a bimodal MWD with clearly separated low- and high-M_w polymer fractions was observed with 1 + 2. The two catalyst systems showed similar hydrogen and hexene responses. Each metallocene precursor showed individual response towards the polymerisation conditions, especially polymerisation temperature, suggesting that interaction between the catalyst active sites was negligible in the studied systems.     

Ion exchange properties of zirconium phosphate phosphite with alkaline earth metal ions.

The ion exchange properties of zirconium phosphate phosphite, a layered compound with asymmetrical layers, towards alkaline earth cations were investigated and compared with those of a-zirconium hydrogenphosphate.

It was found that these cations were easily taken up in the phosphate regionsof_ a-Zr(HPO₄)_{0 7}(HPO₃),.O.5H₂O whereas only Ca²⁺ and Sr²⁺ are directly exchanged from a-Zr(HP0₄)₂.H₂O. The ion exchange mechanism involves a single pnase transition and the solubility of the exchanging cations in the already formed phases. A wide solubility range was found for barium exchange. The interlayer distances and water content of the exchanged forms of zirconium phosphate-phosphite and those of the corresponding phases of zirconium phosphate were compared and discussed on the basis of the structural features of the two hosts.

Zirconium phosphate-phosphite has a relatively low ion exchange capacity (2.5 meq/g) compared to that of the zirconium phosphate (6.64 meq/g)but it is a more facile exchanger for large and hydrated cations.     

Synthesis and electrochemical behavior of ceramic cation-exchange membranes based on zirconium phosphate

Cation-exchange membranes made exclusively from ceramic materials have been synthesized by means of the impregnation of microporous ceramic supports with zirconium phosphate. Changes in the pore size distribution and total pore volume of the supports were provoked by the addition of starch as pore former in the fabrication procedure. This allowed the production of supports with increased effective electrical conductivities and with larger pores available for the zirconium phosphate deposition. An improved functionality for the exchange of cations was given to the ceramic membranes by means of their impregnation with the active particles of zirconium phosphate. The ion-exchange properties of the membranes were increased with further impregnation cycles and the resulting current–voltage curves showed a similar shape to that typical of commercial polymeric ion-exchange membranes. The production of ion-exchange membranes with increased chemical and radiation stability will broaden their applicability for the treatment of specific industrial waste waters, which are very aggressive for the current commercial ion-exchange membranes.     

微波法制备磷酸锆的研究

采用氧氯化锆为锆源、氟化铵为络合剂、磷酸为磷源,在低温（〈100℃）和常压条件下,微波辅助加热法在较短时间内制备得到规则的六角形片状结构Zr（HPO4）2·H2O（简写为α-ZrP）晶体。研究了不同反应物浓度下NH4F与ZrOCl2·8H2O摩尔比、磷酸与ZrOCl2·8H2 O摩尔比、反应时间、反应温度等因素对于合成磷酸锆晶体的影响。产物采用XRD、 SEM和FT-IR表征。以罗丹明B为降解对象,可见光下研究所制备磷酸锆的光催化性能。结果表明,当[ Zr^4＋]=0.02 mol/L, NH4 F/Zr=6和P/Zr=40,微波加热温度90℃,反应时间为30 min时制备的磷酸锆具有良好的光催化活性。