医用羟基磷灰石颗粒的制备与生物学评价

本文采用水热工艺法制备出医用羟基磷灰石（ＨＡＰ）微粉，配方后经造粒，高温烧成工艺制备出骨植填充材料－ＨＡＰ陶瓷颗粒。通过ＳＥＭ分析及生物学性能的试验，表明ＨＡＰ陶瓷颗粒材料作为人体填充材料是安全可靠的，为临床试验及应用提供了必要的实验依据。     

悬浮聚合用HAP／SDBS无机分散体系的作用机理

研究了ＨＡＰ粉末的沉降特性与生成过程，考察了ＨＡＰ粉末和不同表面活性剂配合在苯乙烯单体分散液中的吸附特性，同时研究了ＨＡＰ粉末复合不同表面活性剂的无机分散体系用于苯乙烯单体悬浮聚合时的聚合稳定性。对ＨＡＰ／ＳＤＢＳ无机分散体系用于悬浮聚合时的分散作用机理进行了探讨。简化了用于苯乙烯悬浮聚合用ＨＡＰ的制备方法：取消缓冲体系，缩短陈化时间，室温制备。且制备的分散剂用于聚合时为常量的１／５。     

阻隔性HDPE／MPE／PA1010共混体系的研究

用挤出法以马来酸酐（ＭＡＨ）接枝高密度聚乙烯（ＨＤＰＥ）为增容剂（ＭＰＥ），ＰＡ１０１０为阻隔组分，ＨＤＰＥ为基料，制取了ＨＤＰＥ／ＭＰＥ／ＰＡ１０１０共混材料。研究了挤出温度、ＭＰＥ用量、ＰＡ１０１０含量对其阻隔性能的影响，比较了几种不同渗透体系的吸油率和渗透损失量。     

热压烧结羟基磷灰石生物陶瓷

采取湿化学法制取羟基磷灰石（ＨＡＰ）粉末，热压法烧结陶瓷。瓷体呈半透明。抗压强度可达６８７ＭＰａ，断裂韧性为０．９８ＭＰａｍ＾１／２，比常压烧结分别提高了三倍和一倍。并测定了开口孔率、吸水率和体密度，以及Ｘ－光衍射，电镜观察。     

溶液法马来酸酐接枝EPDM的研究及对尼龙的相容,增韧效应

本文介绍采用溶液法制备马来酸酐（ＭＡＨ）接枝乙丙橡胶（ＥＰＤＭ）以及该接枝物对尼龙（ＰＡ）的相容、增韧效应。研究了引发剂ＢＰＯ和ＭＡＨ用量与接枝率、接枝效率、交量的关系，当ＭＡＨ／ＥＰＤＭ为１０／１００（质量比，下同）时，ＢＰＯ／ＥＰＤＭ的最佳值约为２．２８／１００；固定ＢＰＯ／ＥＰＤＭ为１０／１００时，ＭＡＨ／ＥＰＤＭ的最佳值约为１２．５／１００。由Ｍｏｌａｕ实验表明，ＭＡＨ接枝ＥＰＤＭ／ＰＡ比     

阻隔改性组分PA6对HDPE/PA6合金性能的影响

研究了ＨＤＰＥ／ＰＡ６合金阻隔改性组分ＰＡ６的筛选及其含量对该合金阻隔性能和力学性能的影响。结果表明，在增容剂的条件下，具有适当粘度的ＰＡ６能与ＨＤＰＥ共混制得宏观均匀的合金材料；ＰＡ６含量对共混体系的阻隔性能影响显著；当ＰＡ６占３０份以上时，ＨＤＰＥ／ＰＡ６合金阻隔非极性溶剂的性能大幅度提高，同时，ＰＡ６的加入对合金有一定的增强作用。     

PE—g—MAH对HDPE／PA6共混合金的增容作用

利用ＤＳＣ研究了ＰＥ－ｇ－ＭＡＨ对ＨＤＰＥ／ＰＡ６共混体系的增容作用,并讨论了ＰＥ－ｇ－ＭＡＨ对ＨＤＰＥ／ＰＡ６共混物的混容性能和力学性能的影响。结果表明：ＰＥ－ｇ－ＭＡＨ能有效地增强ＨＤＰＥ／ＰＡ６共混体系两相界面的相互作用,改善ＨＤＰＥ和ＰＡ６的相容性,是效果较好的增容剂。适量的ＰＥ－ｇ－ＭＡＨ的加入可使ＨＤＰＥ／ＰＡ６共混合金的可混性能提高,并有一定的增强作用。     

AA／HAPS共聚物阻垢性能研究

本文合成了一系列ＡＡ／ＨＡＰＳ共聚物，探讨了共聚组成、共聚物浓度、ＰＨ值、钙离子浓度及温度对共聚物组垢率的影响。研究结果表明，ＡＡ／ＨＡＰＳ共聚物具有优异的阻碳酸钙垢和阻磷酸钙垢性能。     

丙烯酸酯胶粘剂聚合物剥离后形态结构的研究

本文考察了从Ｐｙｒｅｘ玻璃上剥离后的各种丙烯酸酯胶粘剂聚合物的形态结构．丙烯酸酯聚合物（丙烯酸－２－乙基已酯（２ＥＨＡ）－丙烯酸（ＡＡ）－醋酸乙烯酯（ＶＡｃ）共聚物）Ｐ（２ＥＨＡ－ＡＡ－ＶＡｃ）的组成比为：２ＥＨＡ／ＡＡ／ＶＡｃ＝１００／０／０（ＥＥＨＡ００００），９５／５／０（ＰＥＨＡ０５００），９２／８／０（ＦＥＨＡ０８００）和８５／５／１０（ＰＥＨＡ０５１０）（ｍｏｌ％）．ＰＥＨＡ００００的剥离类型为伸长的锯齿状；而ＰＥＨＡ０５００和ＰＥＨＡ０８００剥离后在锯齿的边缘呈特征的分支带ＰＥＨＡ０５１０剥离形态呈有规则的锯齿状．用动态热力学分析方法，表面张力试验法和荧光探测技术探测了不同类型丙烯酸胶粘剂聚合物的剥离形态．关键词     

用活性添加剂缩短过磷酸钙的熟化期

添加非离子型表面活性剂ＲＡ、ＲＢ、ＲＣ、ＲＤ、ＲＥ，阴离子表面活性剂Ｐｃ和Ｃ－ＯＨ等活性剂可缩短过磷酸钙熟化期，其中Ｃ－ＯＨ活性剂熟化期最短，可在４８￣９０ｈ之内结束。磷矿中Ｐ２Ｏ５转化率可达９５％以上。     

Influence of iron doping towards the physicochemical and biological characteristics of hydroxyapatite

Hydroxyapatite (HAP) is the naturally occurring mineral form of calcium apatite and the most studied material as a bone substituent. Considering HAP's inherent properties, this study explored changes in HAP's characteristics from doping with other metals such as Fe. To form pure HAP and Fe-HAP with different amounts of Fe, we used the hydrothermal approach, and the composites that formed were thoroughly analyzed for their crystallinity, surface bonding, morphology, magnetic behavior, mechanical strength, biocompatibility, hemocompatibility, and in vitro cytotoxicity. The powder XRD studies confirmed the samples' crystallinity, and the lowest crystalline size was 19.7 nm in 10Fe-HAP. The FTIR analysis confirmed the formation of HAP by the hydroxyl, phosphate, and carbonate groups. The FESEM demonstrated that the morphology of the pure HAP was rod-shaped, which transformed into spheres after Fe doping. The EDS analysis confirmed the successful formation of HAP and Fe-HAP composites. The magnetic studies indicated the diamagnetic behavior of the pure HAP, while the Fe-doped HAPs had a superparamagnetic nature with saturation magnetizations (M_s) of 2Fe-HAP, 4Fe-HAP, and 10Fe-HAP at 0.0062, 0.0092, and 0.029 emu/g respectively. Assessment of the mechanical properties, biocompatibility, hemocompatibility, and cytotoxicity indicated that the Fe-doped HAPs were superior to the pure HAP, and among the Fe-HAPs, the 10Fe-HAP) had the highest amount of Fe and the best characteristics. The studies also indicated that Ca²⁺ interactions influenced the cells via HAP doping with that of Fe, equally increasing the physicochemical and biological properties.     

Preparation and property of porous hydroxyapatite as an inorganic dispersant used in suspension polymerization

The porous hydroxyapatite (HAP) for suspension polymerization dispersant was prepared using calcium carbonate and phosphoric acid as raw materials. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET nitrogen adsorption. The results show that the prepared HAP has a porous structure, low particle density, large specific surface area, uniform particle size and does not agglomerate easily between the particles. The preparation conditions for the HAP were optimized as follows: solid content of calcium carbonate aqueous suspension 90 g/L, concentration of phosphoric acid 1.0 mol/L, reaction/aging temperature 50°C, and aging time 3 h. The HAP prepared under optimal preparation conditions has 106.8 m²·g^-1 of specific surface area, which is about 1.5–1.8 times as much as that of Japanese HAP or commercial HAP. Its application result in the suspension polymerization of styrene show that the porous HAP dispersant has high surface activity, excellent suspension dispersibility and stability and can markedly improve the quality of polystyrene beads.     

Influence of strontium and niobium on the physical and biological performance of hydroxyapatite as a bioactive coating on implant materials

The coating of hydroxyapatite (HAP) on the surface of bio-inert metallic implants to augment their bioactivity is in use for the last two decades. Substitution of various materials in HAP further improves the functionality of these coatings. We demonstrate coating of Ti6Al4V alloy sheets with strontium and niobium reinforced HAP using microwave (MW) irradiation technique. Physical characterization revealed, uniform semicrystalline hydroxyapatite coating with enhanced surface roughness and microhardness. The increased surface roughness was accompanied by higher wettability and more protein adsorption. Electrochemical corrosion assessment showed a dramatic increase in corrosion potential and a noticeable decline in corrosion current density suggesting an enhanced anticorrosive behaviour. These implants also exhibited improved hemocompatibility and bacteriostatic properties. Cell viability and confocal microscopy studies of the coated samples showed enhanced cell attachment on the surface. We propose microwave irradiation as a fast and hassle-free alternative for one-pot synthesis and deposition of ionic substituted HAP on metallic implants.     

The effect of lignin on the structure and characteristics of composite coatings electrodeposited on titanium

Composite coatings based on lignin, obtained by electrophoretic deposition (EPD) on titanium, were investigated. The aim of this work was to produce hydroxyapatite/lignin (HAP/Lig) coatings on titanium and to investigate the effect of the lignin concentration on microstructure, morphology, phase composition, thermal behavior and cytotoxicity of the HAP/Lig coatings. An organosolv lignin was used for the production of the composite coatings studied in this research. The properties of HAP/Lig coatings were characterized using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FT-IR) and X-ray photoelectron spectroscopy (XPS), as well as the MTT test of cytotoxicity. The results showed that higher lignin concentrations protected the HAP lattice during sintering, thereby improving the stability of the HAP/Lig coatings. The cell survival of peripheral blood mononuclear cells (PBMC) after proliferation indicates that the HAP/Lig coating with 1 wt% Lig electrodeposited on titanium was non-toxic with significant promise as a potential bone-repair material.     

Photografting of methacrylic acid onto hydroxyapatite particles surfaces

The unsaturated functional groups (C?C) were introduced onto hydroxypatite (HAP) particles surfaces by esterification reaction between hydroxyl groups on the HAP surface and methacrylic acid (MAA). Then, graft polymerization of MAA onto the esterified HAP particles surfaces was carried out by ultraviolet light (UV) initiation. The structure of the surface‐esterified and grafted HAP was studied by ESCA, FTIR, Scanning Electron microscopy, laser particle sizes analyze, esterification, and graft degrees tests. The results show that poly(methyl acrylic acid) (PMAA) is successfully inserted onto HAP particles surfaces by covalent bond linkage. The esterification degree between MAA and HAP particles increases with reaction temperature and time, and tends to level off at about 6 h under 90°C. The graft degree of MAA onto HAP particles with 1.14% esterification degree and its average particle sizes increase with UV initiation polymerization time, and to reach a maximum at 25 min under 40°C, then decrease as irradiation time further increases. The surfaces of the grafted HAP particles become rough and loose. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

羟基磷灰石纳米棒的可控制备及其催化一氧化碳氧化性能

采用简单的一步水热法,以赖氨酸为沉淀剂,通过改变赖氨酸浓度,合成不同尺寸的羟基磷灰石(HAP)纳米棒,负载质量分数3%Ag制备Ag/HAP催化剂。利用Ag与HAP之间的强相互作用将Ag纳米粒子分散在HAP载体表面,使其具有较好的催化活性。活性测试发现,赖氨酸浓度为0. 20 mol·L~(-1)时,制备的Ag/HAP催化剂催化性能最好,在空速为60 000 mL·(g·h)~(-1)条件下,CO的完全转化温度为190℃。XRD和SEM表征结果表明,赖氨酸浓度对Ag/HAP催化剂的结构和性能影响较大。UV-vis、H_2-TPR和XPS测试结果表明,活性组分Ag主要以Ag~0和Ag~+的形式存在于HAP载体上,其中Ag0作为主要催化活性中心,使Ag/HAP催化剂在CO氧化反应中保持较高的活性。     

Mineralization of hydroxyapatite on a polymer substrate in a solution supersaturated by polyelectrolyte

In this article, a new method to construct composites of hydroxyapatite (HAP) and polymer material is introduced. A previously developed method for mineralization of CaCO₃ on a polymer substrate was applied to HAP. A solution that contained Ca²⁺, PO₄^3–, and OH‐ ions was supersaturated with polyacrylic acid (PAA) that, at the same time, formed a polymer complex with the substrate, a polyvinyl alcohol (PVA) film, at the substrate surface. In this thin surface layer, nucleation of HAP took place. Subsequently, the disklike domains of HAP that were generated spread until they covered the PVA film surface. By regulating the pH of the supersaturated solution at around 7.4, the domain size decreased and the quantity of deposited material increased. Approximately 20 mg of HAP coating was obtained on a PVA film of 1 cm radius when the film was soaked in single 200 mL batch of the supersaturated solution for 21 days. The junction between HAP layer and PVA substrate film was found to be very firm. When a crosslinked PVA/PAA was used as the substrate, the film swelled in the supersaturated solution to form a hydrogel. Then mineralization took place within the gel, and a transparent monolithic composite of HAP and the polymer network was obtained. In 13 days, the weight increase was 29 mg, which corresponded to a 71 wt % HAP mineralization ratio of the composite. By changing crosslinking degree and HAP mineralization ratio, the flexibility of composite will be controlled in a wide range. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1465–1470, 2006     

Influence of irradiation parameters on the curing and interfacial tensile strength of HAP printed part fabricated by SLA-3D printing

In this paper, the curing and the interfacial tensile strength of a hydroxyapatite (HAP) printed part, fabricated by stereolithography (SLA), are systematically evaluated. First, a stable HAP paste was developed with a viscosity suitable for SLA-3D printing. In the curing process of SLA-3D printing, an evident laser removal phenomenon occurred on the upper surface of the cured HAP paste, which was not mentioned in other studies. Therefore, the influence of irradiation parameters on the curing characteristics of HAP paste was investigated, while a modified critical laser exposure inequation was established, to derive the curing range of HAP paste under a UV spot. Next, the influence of irradiation parameters on the interfacial tensile strength of HAP printed part was tested and analyzed in detail. Ideally, the laser removal site formed on the cured surface would increase the contact area with the next layer and facilitate a stronger mechanical bond between layers.     

Swelling behavior of hydroxyapatite‐filled chitosan–poly(acrylic acid) polyelectrolyte complexes

A family of hydroxyapatite (HAP)‐filled chitosan (CHI)–poly(acrylic acid) (PAA) polyelectrolyte complexes was prepared for the development of a degradable biocompatible organic matrix with nascent HAP that will degrade in vivo over a period of time. The effects of complexation on the degradation profile of the composites as well as the interaction between the CHI–PAA matrix and HAP in the composite system were evaluated by studying the swelling behavior of these composites in phosphate‐buffered saline (PBS) by varying their CHI–PAA ratio and HAP content. All composite systems showed a general trend of three stages of swelling with the variation in the degree of equilibrium swelling. The percentage weight gain initially decreased in a linear way with increases in the HAP weight percentages, leading to a first equilibrium swelling, represented by the plateau; further increased to a greater extent; and finally stabilized. The CHI/PAA/HAP composites were stable in PBS up to a period of more than 45 days whereas the 50/50 CHI/PAA control sample showed a single equilibrium attained after a period of 288 h. Further exposure of the specimen to the medium led to its disintegration. It was also observed that, even though CHI and PAA were capable of binding HAP, because of the lack of efficient binding, the integrity of the CHI–HAP and PAA–HAP composites were lost within 48 h. The 50/50/80 CHI/PAA/HAP composition showed the minimum amount of swelling in the series. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4716–4722, 2006     

Development of hydroxyapatite coatings on laser textured 316 LSS and Ti-6Al-4V and its electrochemical behavior in SBF solution for orthopedic applications

The current work focused on the development of hydroxyapatite (HAP) coating on laser textured metallic implants using electrophoretic deposition. HAP was synthesized by sol-gel technique and its phase purity and surface morphology were confirmed by FT-IR, XRD and SEM analysis. 316 L SS and Ti-6Al-4V metal implants were polished and the surface was modified using Nd-YAG laser operating at a pulse interval of 10 ns at various overlapping rate of 0%, 25% and 50%. The laser treated surface was characterized for its surface roughness using surface profilometry and surface morphology. The surface roughness of the metallic implants was increased by increase in the overlapping rate. The prepared HAP powder was electrophoretically deposited on bare and laser textured Ti-6Al-4V and 316 L stainless steel followed by vacuum sintering at 300 °C for 2 h. Scratch analysis results showed an improvement in adhesion strength for the HAP coatings on laser treated specimens than untreated metal. Corrosion efficiency of the coated samples was studied in SBF solution using EIS and potentiodynamic polarization studies. The result from the corrosion experiments proved increased corrosion resistance property of laser textured coated samples when compared to bare alloy due to higher adhesion of HAP coating on the metal surface.