绿色环保型聚天冬氨酸阻垢剂合成与阻垢性能

以马来酸酐(MA)与氨水为原料热缩聚法合成聚天冬氨酸阻垢剂,分别考察了原料配比、热缩聚温度和热缩聚时间对产物的阻垢性能的影响,得到最佳合成条件:n(MA)∶n(NH3)为1∶2.0,热缩聚温度240℃,热缩聚时间3 h。当实验水中Ca2+质量浓度为240 mg/L时,聚天冬氨酸阻垢剂的阻垢率达到72%,适用于低矿化度的工业循环冷却水和油田回注水。同时使用L-天冬氨酸对聚合物开环改性,其阻垢率可达到87%。     

聚天冬氨酸及其复配物对硫酸钙的阻垢性能

以L-天冬氨酸为原料，热聚合成聚天冬氨酸酐，水解得到聚天冬氨酸的钠盐。采用凝胶色谱法(GPC)测定了聚天冬氨酸的相对分子质量。研究了聚天冬氨酸及其复配物的阻CaSO4垢性能。实验表明：聚天冬氨酸在投加质量浓度为4mg／L时，阻垢率达到90％，优于常用的阻垢剂聚马来酸和聚丙烯酸。聚天冬氨酸与三聚磷酸钠的复配物在投加质量浓度为5mg／L时，阻垢率达到90％，与柠檬酸三钠的复配物的阻垢率达到88％。聚天冬氨酸及其复配物均具有一定的耐温性能，且聚天冬氨酸优于其复配物。     

聚天冬氨酸与丙烯酸共聚物复配物阻垢性能研究

以马来酸酐和碳酸铵为原料采取固相熔融法合成聚天冬氨酸。为了降低水处理运行成本,研究了聚天冬氨酸与丙烯酸共聚物复配阻垢性能。说明聚天冬氨酸能部分取代目前常用的共聚物阻垢剂。     

聚天冬氨酸对碳酸钙阻垢性能的研究

本文研究了不同因素对可生物降解的新型聚合物阻垢剂聚天冬氨酸抑制碳酸钙垢性能的影响。结果表明：在低投加量的情况下,分子量为4000的聚天冬氨酸具有最为优良的阻垢性能。聚天冬氨酸可应用于高钙离子浓度、高温和pH较高的水系统。在高温水系统中长时间停留,对碳酸钙仍有较强的抑制作用。     

聚天冬氨酸复配物及其阻垢缓蚀性能

通过合成丙烯酸-丙烯酸乙酯-衣康酸（AA-AE-IA）三元共聚物阻垢分散剂,开发出一种具有优良阻垢分散和缓蚀性能的新型聚天冬氨酸复配物（PASP＋AA-AE-IA＋PBTCA）,考察了不同条件下聚天冬氨酸复配物对碳酸钙和硫酸钙的阻垢性能。利用扫描电子显微镜对碳酸钙晶型进行了分析,结果表明：聚天冬氨酸复配物可使碳酸钙晶体发生明显的扭曲现象,碳酸钙结晶更加细小分散。     

聚天冬氨酸与木质素磺酸钠复配物的阻垢性能

通过静态阻垢法研究了国产聚天冬氨酸(PASP)与造纸工业的副产品木质素磺酸钠(SLS)投加量对碳酸钙、硫酸钙、硅酸钙的阻垢性能的影响。结果表明:PASP与SLS的配比质量浓度为2.0mg/L和5.0mg/L时,复配物具有优良的阻垢性能,且该复配物适用于高钙离子浓度、较高pH值的水系统中,并且可以在较高温度的水系统中长时间停留。该复配体系降低了环保型水处理剂PASP的用量,而且阻垢性能较单纯使用PASP优异。     

新型聚合物阻垢剂聚天冬氨酸的合成与性能

对新型水处理剂聚天冬氨酸的合成、热稳定性及阻垢性能等进行了研究。研究结果表明 :聚天冬氨酸的合成为无催化剂的L 天冬氨酸缩聚反应。相对分子质量为 40 0 0的聚天冬氨酸具有最为优良的阻垢性能 ;药剂投加量仅为 0 2mg/L时 ,对碳酸钙的阻垢率就达到 88% ,阻垢率达到 10 0 %时药剂浓度仅为 2 0mg/L ;增加聚天冬氨酸阻垢剂浓度使阻垢率随着Ca2 +浓度增加而下降的趋势变缓。聚天冬氨酸是一种可应用于高温、高钙离子浓度水系统的聚合物阻垢剂。     

聚天冬氨酸与磷（膦）系复配物阻垢性能研究

以马来酸酐和碳酸铵为原料采取固相熔融法合成聚天冬氨酸,为了降低水处理运行成本,并研究了聚天冬氮酸与磷（膦）系复配物阻垢性能。说明聚天冬氨酸能部分取代目前常用的磷（膦）系阻垢剂。     

阻垢剂阻垢性能比较

文章通过碳酸钙沉积法对PBTCA、ATMT、HEDP、PAPE、HPMA、AA/AMPS、HPMA、PESA、PSAP的阻垢性能进行测定,分别用螯合阻垢性能及非粘附阻垢性能表示各阻垢剂的阻垢能力。并提出非粘附阻垢性能比螯合阻垢性能更能反映阻垢剂的阻垢能力。     

聚天冬氨酸衍生物及其复配物的阻垢性能研究

聚天冬氨酸（PASP）是一种可生物降解的水溶性氨基酸聚合物，在工业领域应用广泛，是一种很有发展前景的生物高分子材料。从20世纪90年代开始成为水处理药剂研究和开发的热点，在工业循环冷却水领域可以替代现在使用的聚丙烯酸，但其阻CaCO3垢，Ca3（PO4）2垢的能力都不突出，其应用受了很大限制。为改善聚天冬氨酸的阻垢性能，我们参考文献，用2．氨基乙醇与聚琥珀酰亚胺（PSI）反应，把羟基引入到PASP分子结构中合成了聚天冬氨酸的衍生物，并将其与药剂PBTCA复配，结果表明复配药剂具有很好的协同效应，具有良好的阻垢性能，因此可作为阻垢分散剂而广泛应用于循环冷却水处理中。     

Functionalization of multiwalled carbon nanotubes with amphiphilic poly(aspartic acid)

A new method to functionalize multiwalled carbon nanotubes (MWNTs) with amphiphilic poly(aspartic acid) was investigated. The amphiphilic polymer (PASP‐C16) was synthesized by thermal condensation and aminolysis by hexadecylamine, followed by hydrolysis of the remaining succinimide units in the polymer backbone. The functionalization of MWNTs was achieved by physical adsorption of the biopolymer onto the surfaces of MWNTs. Ultraviolet‐visible ( UV‐vis) spectra showed that the functionalized MWNTs had a good aqueous dispersity and solubility. The interaction of PASP‐C16 with MWNTs was investigated by analyzing X‐ray diffraction (XRD) patterns, circular dichroism (CD), spectra and high‐resolution transmission electron microscopy ( HRTEM ). From the XRD patterns, it can be known that the aggregate of PASP‐C16 due to intermolecular interaction between hexadecyl chains has been reduced when the polymer interacting with MWNTs. CD spectra indicated that the interaction of hexadecyl chains of PASP‐C16 with the wall of MWNTs is the major interaction between PASP‐C16 and MWNTs, and MWNTs were covered by the poly(aspatic acid) backbone. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

Preparation and physical properties of N‐defunctionalized derivatives of poly(aspartic acid)

A number of N‐substituted poly(aspartic acid)s was prepared under mild conditions using the silylation–alkylation technique. Their physical properties were studied. Free swelling capacity (FSC) tests were performed for polymers obtained by crosslinking the parent poly(aspartic acid) as well as its defunctionalized derivatives. The hypothesis that H‐bonding is critical in superabsorbency was demonstrated. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 85–90, 2001     

Degradation behavior of hydrogel based on crosslinked poly(aspartic acid)

The degradation behavior of hydrogel based on poly(aspartic acid) (PASP) which crosslinked by 1, 6‐hexamethylene diamine (HD) was studied in α‐chymotrypsin solution. The degradation behaviors of PASP under different crosslinking levels were evaluated as a function of biodegradation time by monitoring the changes of crosslinking density, molecular weight, rheological behavior, interior morphology, mass loss, and swelling ratio. It was found that the degradation behaviors relied heavily on the crosslinking density which calculated from the Flory‐Rehner equation. A pseudo first‐kinetic equation was proposed to model the mass loss behavior and the degradation rate constant was calculated under different crosslinking levels. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Electrospun poly(aspartic acid) gel scaffolds for artificial extracellular matrix

Biocompatible synthetic polymer gel scaffolds for tissue engineering and regenerative medicine were prepared by reactive electrospinning. Protein‐like nano‐ and microfibres from chemically crosslinked polysuccinimide were obtained. Fibrous poly(aspartic acid) gels with size similar to that of extracellular matrix were obtained by hydrolysis of the polysuccinimide gel fibres. The effects of process parameters on fibre morphology (diameter, swelling degree) and chemical structure were investigated. Sub‐micrometre‐sized biocompatible fibrous scaffolds from a poly(amino acid) is a novel approach with great promise in several biomedical applications due to the tailor‐made synthetic nature, extreme purity and possibility of production on a large scale. © 2014 Society of Chemical Industry     

Innovative spectral investigations on the thermal-induced poly(aspartic acid)

Two-dimensional (2D) correlation FTIR spectroscopy was used to investigate the dynamic mechanism of poly(aspartic acid) during the heating process. According to the 2D asynchronous correlation spectra, the CO vibration band of Amide I was separated into three peaks at 1637, 1645 and 1677 cm⁻¹, assigned to α helical, random coil and β antiparallel conformation, respectively. And α helical structure would transform into the more ordered and stable conformation of β antiparallel in heating. In the region of 3700-2700 cm⁻¹, the H-contained groups were analyzed; the loosening of hydroxyl is found to change prior to the NH-related hydrogen bonds and the conformational reorganization of hydrocarbon chains.     

Comparison of poly(aspartic acid) hydrogel and poly(aspartic acid)/gelatin complex for entrapment and pH‐sensitive release of protein drugs

Biodegradable poly(aspartic acid) (PASP) hydrogel and PASP/gelatin complex were prepared to evaluate their potential application as pH‐sensitive matrices for controlled protein release. Entrapment of myoglobin (Mb) and its release were compared between the two types of carriers. It was found that incorporation of Mb into PASP hydrogel strongly depended on the medium pH and NaCl concentration, and was time‐consuming. However, complete entrapment of Mb into PASP/gelatin complex was found within pH ranged from 2.5 to 4.0, which was concomitant with the formation of PASP/gelatin complex. By adjusting Mb feed ratio, Mb entrapment in the complex can be up to 31.54% (by weight) with high loading efficiency (96.2%). Gradual release of Mb from PASP hydrogel was observed within pH 2.0–7.4, while Mb release from PASP/gelatin complex was negligible within pH 2.0–4.2 for 4 days. In addition, pulsatile Mb release can be achieved by combining polyanhydride with pH‐sensitive PASP/gelatin complex, while the device composed of polyanhydride and PASP hydrogel is mechanically unstable. PASP/gelatin complex formed by electrostatic interactions is superior to the single‐component PASP hydrogel synthesized by chemical cross‐linking as pH‐sensitive matrices for controlled protein release when entrapment of proteins and pH‐sensitivity of protein release are concerned. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Salt-, pH- and temperature-responsive semi-interpenetrating polymer network hydrogel based on poly(aspartic acid) and poly(acrylic acid)

In this study, a novel salt-, pH- and temperature-responsive semi-interpenetrating network (semi-IPN) hydrogel, composed of poly(aspartic acid) (PAsp) and poly(acrylic acid) (PAAc), was prepared. PAsp/PAAc semi-IPN hydrogel being ionic in nature, the swelling behavior was significantly influenced by various swelling medium. The structure of the triply responsive hydrogel was studied by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), and the salt-, temperature- and pH-sensitivities were investigated through measuring equilibrium swelling ratios in various environmental solutions. The results indicate that there is a structure of polyelectrolyte complex in the hydrogel, and that the responsive behaviors of this hydrogel to alternating changes in inorganic salt (different physiological bio-fluids), pH and temperature are improved because of the incorporation of PAsp. In addition, during the repeatable swelling and shrinkage period, the semi-IPN hydrogel shows suitable mechanical strength. The salt-, pH- and temperature-responsive hydrogel will have wider applications in biomedical areas.     

聚醚改性聚天冬氨酸减水剂的制备及其性能

摘要：以聚琥珀酰亚胺（PSI）和端氨基聚醚M2005（M2005）为原料,合成了聚醚改性聚天冬氨酸减水剂（PEMPASP）,采用FTIR对PEMPASP进行了表征,探讨了不同减水剂及其用量对水泥净浆流动度和胶砂强度的影响;通过对TOC、Zeta电位、XRD以及TG-DSC分析,研究了PEMPASP减水剂的作用机理。结果表明,当采用nPSI:nM2005为1:0.14所制备的PEMPASA,在掺量为水泥的0.35%时,水泥的净浆流动度比掺加聚天冬氨酸（PASP）的水泥净浆流动度提高了189%,在用量为0.25%时,水泥胶砂抗折强度比空白水泥增长了15.6%,比含有PASP的水泥胶砂增长了17%;由于在PASP分子上引入长侧链聚醚链,改变了减水剂分子上的电荷密度和侧链结构,影响了减水剂对水泥颗粒的静电作用和位阻作用,进而改善了吸附、分散以及水泥的水化作用,提高了减水剂的综合性能。     

Tailorable polyelectrolyte protein complex based on poly(aspartic acid) and bovine serum albumin

Protein–polyelectrolyte complexes (PPC) are playing an important role in a variety of chemical and biological processes, such as protein separation, enzyme stabilization, and polymer drug delivery. The present investigation is focused on evaluation of the PPC formation between a synthetic polypeptide (poly(aspartic acid) – PAS) and a natural protein (bovine serum albumin – BSA). The PPC obtained from PAS and BSA in different ratio was investigated by corroboration of various techniques of characterization as: spectroscopy, microscopy, thermogravimetric analysis, dynamic light scattering (DLS), and zeta potential determination, measurements which were performed in static and/or dynamic conditions. The static contact angle of the sample films was also determined in order to evaluate the changes brought upon surface free energy of the prepared PPCs in interdependence with the complexes composition. The critical conditions for complex formation in BSA–polyelectrolyte systems were underlined. The phenomenon was better evidenced in case of a ratio of 1/1 wt between the two polymers, both in static and/or dynamic conditions.     

不同分散剂对聚天冬氨酸吸水树脂性能的影响

在聚天冬氨酸(PAsp)吸水树脂制备过程中,分别以去离子水、甲醇、乙醇、正丁醇为分散剂加入到聚琥珀酰亚胺(PSI)溶液中使之成为均匀体系,在该体系中加入交联剂1,6-己二胺制备了具有三维网络结构的环保型高吸水树脂,并利用FTIR、SEM、TG等手段对其微观结构进行了测试。通过对比4种分散剂对PAsp吸水树脂吸液性能的影响,得出以下结论:不论是何种分散剂,适量的单独加入均可显著提高吸水树脂的吸液倍率,其中以去离子水为优,在蒸馏水和生理盐水中的吸液倍率分别达945 g/g和94 g/g;以正丁醇作分散剂可明显提高吸水树脂的吸液速率,吸液7 h即可达溶胀平衡;以m(去离子水)∶m(正丁醇)=7∶3的混合溶剂作为分散剂时,树脂的吸水性能较纯水与纯正丁醇要好,吸水6 h后即达吸液平衡,吸水倍率可达1 004 g/g;PAsp树脂的吸水性能随着干燥次数的增加而逐渐下降,干燥5次后树脂的吸水倍率仍能达到400 g/g,说明PAsp树脂具有较好的重复吸水性能。