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1.
以马来酸酐(MA)、丙烯酸(AA)、丙烯酰胺(AM)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为原料,通过自由基溶液共聚合法,合成了MA/AA/AM/AMPS四元共聚物阻垢剂。红外光谱(FT-IR)结果表明共聚物分子链上同时含有羧酸基、酰胺基和磺酸基等基团;扫描电镜(SEM)分析表明MA/AA/AM/AMPS抑制了碳酸钙和硫酸钙垢的生长。探讨了共聚物用量、钙离子浓度、体系pH值和温度对MA/AA/AM/AMPS阻碳酸钙和硫酸钙垢的影响。结果表明,合成产物对碳酸钙和硫酸钙具有优良的阻垢性能,且适用于高温循环水处理。  相似文献   

2.
以本体聚合方法合成了可生物降解的多元氨基酸共聚物,并采用差示扫描量热分析(DSC)、热重(TGA)和X射线衍射(XRD)等手段对所合成的共聚物进行了表征.结果表明,所合成的多元氨基酸共聚物在常温下可微溶于某些非质子有机溶剂及质子强酸,提高温度可明显提高其溶解性;所合成共聚物为一种半结晶性聚合物,其结晶部分主要为6-氨基...  相似文献   

3.
以聚乙二醇为原料,采用四步反应,合成了二碳酸二叔丁酯单保护的氨基聚乙二醇(BOC-PEG-NH2);并以DOe-PEG-NH2为引发剂,引发丙交酯开环聚合,得到了叔丁氧基酰胺基聚乙二醇-聚乳酸嵌段共聚物(BOC-PEG-PLA).在三氟乙酸二氯甲烷溶液中,脱去保护基团,得到了端氨基聚乙二醇-聚乳酸嵌段共聚物(NH2-PEG-PLA).采用核磁共振氢谱(1H-NMR)、紫外光度仪(UV)表征各聚合物的结构,由凝胶色谱仪(GPC)测定嵌段共聚物的分子量以及分子量分布.结果表明:合成的氨基引发在无催化剂条件下能够引发丙交酯开环聚合,制得分子量高、分子量分布窄的双亲性共聚物.通过三氟乙酸脱保护得到了端氨基聚乙二醇-一聚乳酸(NH2-PEG-PLA),且对分子量没有影响.  相似文献   

4.
以丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、二烯丙基二甲基氯化铵(DADMAC)为单体合成高吸水树脂(SAR)。利用疏水单体丙烯酸丁酯(BA)对高吸水树脂进行改性,并与丁腈橡胶共混制备吸水膨胀橡胶(WSR)。研究了P(AA/BA)含量对SAR、WSR吸水性能及WSR力学性能的影响。结果表明:P(AA/BA)含量达到SAR质量的33.3%(质量分数,下同)时,SAR的吸水率仅降低了8.49%;当P(AA/BA)含量为23.1%时,WSR的拉伸强度和断裂伸长率均达到最大值,吸水性能达到最佳,WSR质量流失率降低到5.8%。P(AA/BA)的引入改善了SAR和丁腈橡胶的相容性,提高了WSR的使用性能。  相似文献   

5.
以6-氨基己酸(6-AC)、己二酸(AA)和乙二醇(EG)为原料,采用熔融缩聚法合成了可生物降解聚酯酰胺(PEAs),对处理提纯后的共聚物用红外光谱进行了结构表征;利用差示扫描量热法表征了共聚物的熔融过程和结晶过程,并研究了产物的吸水性和水解降解行为。结果表明,红外光谱图中共聚物中酯键吸收峰的强度随着酯含量的增加而增强;聚合物的熔点(Tm)、熔融焓(ΔHm)和结晶温度(Tc)、结晶焓(ΔHc)随着酯含量的增加而明显降低。共聚物的组成对吸水率影响不大,其降解速率随酯含量的增加而加快;共聚物在酸性溶液中降解速率最快,在碱性溶液中降解速率次之,在近于中性溶液中降解速率最慢。  相似文献   

6.
通过共混法制备了含辣素衍生结构聚合物的抑菌性聚醚砜超滤膜.首先,用N-(5-甲基-3-异丁基-2羟基-苄基)-丙烯酰胺(MBHBA)和丙烯酸(AA)、甲基丙烯酸甲酯(MMA)制备了三元共聚物P(A-M-M),并通过红外光谱证实了聚合物的合成;然后考察了铸膜液中三元共聚物的质量浓度对所制备超滤膜性能的影响.结果表明,当P(A-M-M)质量分数为1%时,改性膜具有较高的综合性能:纯水通量和BSA截留率分别为183.8 L/(m~2·h)和93.8%,与基膜相比略有提高;同时亲水性大幅增加,水静态接触角仅为57°,比基膜降低了17°;抑菌率达到了76%,远高于基膜的抑菌率(20%).  相似文献   

7.
乳胶共混是指将不同玻璃化转变温度(Tg)的共聚物乳胶按照一定比例混合,已成为解决乳胶低温成膜和高力学性能之间矛盾的一项重要技术.采用半连续预乳化工艺合成了高Tg(约40℃)的P(MMA/BA/AA)乳胶和低Tg (约-40℃)的P(2-EHA/BMA/AA)乳胶;通过对不同比例的P(MMA/BA/AA)/P(2-EHA...  相似文献   

8.
合成了含有易交联极性基团 -COOH的新型 6FDA型聚酰亚胺共聚物 (6FDA -TM PDA/DABA) .6FDA(4,4’ -六氟亚异丙基 -邻苯二甲酸酐 )为二酐单体 ,TMPDA(2 ,4 ,6 -三甲基 - 1,3-苯二胺 )和DABA(3,5 -二氨基苯甲酸 )为二胺单体 .采用乌氏粘度计、DSC(差分扫描量热 )和TGA(热重量分析 )测定了共聚物的比浓粘度、Tg(玻璃化转变温度 )和Td(热分解温度 ) .比浓粘度均高于 0 36 ,说明合成的聚合物有较大的分子量 .Tg 在DSC升温至 4 0 0℃时测量不到 ,Td 均在 5 2 0℃以上 ,显示出合成的共聚物有很好的热稳定性 .在 30℃和 10 132 5Pa下测试了摩尔比为 3∶1、9∶1(TMPDA∶DABA)共聚物的H2 、CO2 和N2 的纯气渗透系数 .结果显示两种共聚物均有很高的渗透系数和CO2 /N2 的理想分离系数 .其中 6FDA -TMPDA/DABA 9∶1体系的CO2 纯气渗透系数达到 1 12 5× 10 - 13m3·m/ (m2 ·s·Pa)  相似文献   

9.
以4,4′-二(β-萘氧基)二苯砜(BNODPS),2,5-二氯对苯二甲酰氯(DCTPC)和二苯醚(DPE)为单体,通过亲电缩聚反应,合成了一系列主链含萘环的新型聚芳醚酮砜.经IR、DSC和WAXD等方法对共聚物的研究表明,随着BNODPS结构单元含量的增加,共聚物的玻璃化温度(211~224 ℃)和溶解性逐渐提高,而其熔融温度、结晶度和热分解温度均逐渐下降,但仍具有较高的耐热性.  相似文献   

10.
采用迈克尔加成反应制备了单体2,7-二溴-9,9-二(丙酸二甲氨基乙酯)芴(FDMAEA);采用Suzuki偶合反应制备了不同FDMAEA结构单元含量的醇溶性9,9-二(丙酸二甲氨基乙酯)芴-9,9-二辛基芴共聚物(PFDMAEA)。通过核磁共振、凝胶渗透色谱、溶解性测试、紫外-可见光光谱、荧光发射光谱等对其进行了分析研究。结果表明,成功合成了2,7-二溴-9,9-二(丙酸二甲氨基乙酯)芴及9,9-二(丙酸二甲氨基乙酯)芴-9,9-二辛基芴共聚物。该共聚物在极性溶剂,如甲醇中具有良好的溶解性。由于含有DMAEA支链的PFDMAEA主链容易扭曲,共轭长度变短,共聚物的紫外吸收光谱和荧光光谱随着FDMAEA含量的增加而发生蓝移。荧光发光光谱研究表明,溶剂的极性、溶液的浓度、温度和pH值对共聚物的发光性能有很大的影响。随着溶剂极性增大,共聚物的荧光发射强度不断增加。荧光发射强度随溶液浓度的增加先增加后降低,随着溶液温度的上升而降低。当溶液pH值由1增大到14时,荧光强度不断降低,直至淬灭。  相似文献   

11.
Study of cement mortars modified by emulsifier-free latexes   总被引:3,自引:0,他引:3  
Cationic copolymer latex of vinyl acetate (VA) with methacryloxyethyl trimethylammonium chloride (MTC) and anionic copolymer latex of VA with sodium acrylate (SA) were prepared via emulsifier-free emulsion copolymerization. Modifications of cement mortars by these copolymer latexes were studied, and the results were compared with mortars modified by homopolymer of VA (PVA) as well as with blank mortars. The experimental results showed that flow of the mortars modified by PVA homopolymer and P(VA–MTC) copolymer latexes were increased compared with the blank, whereas a decrease was observed for that modified by P(VA–SA) anionic copolymer latex; a volume expansion was detected in polymer modified mortars by PVA and P(VA–MTC), while no volume expansion was observed in the anionic P(VA–SA) modified mortars; the flexural strength of mortars modified by P(VA–MTC) increased by 79.5% compared to unmodified mortars after 5 day water curing plus 21 day air curing. This value reached 95% when the curing process was followed by a supplementary 24 h vacuum curing. These polymer modified mortars were then subjected to hydration analysis through X-Ray diffraction (XRD). Mechanisms of the mortar modification are discussed based on the characterization results.  相似文献   

12.
利用溶液聚合制备了离子型疏水缔合水溶性共聚物P(AM/AMPS/C11AM),在共聚物结构中引入了既带有疏水长链又带有可离子化的基团,红外光谱确认了所合成的共聚物为目标共聚物;P(AM/AMPS/C11AM)系列共聚物溶液的表观黏度与共聚物浓度有很大关系,即使在极低的共聚物溶液浓度下也具有很好的增粘效果;在一定温度,一定pH值和表面活性剂的条件下,研究了系列共聚物溶液行为,结果与接枝疏水单体改性的丙烯酰胺是不同的。荧光光谱研究证实了共聚物在水溶液中的缔合行为。  相似文献   

13.
Deoxyribozymes (DNAzymes) having RNA-cleaving activity have widely been explored as tools for therapeutic and diagnostic purposes. Both the chemical cleaving step and the turnover step should be improved for enhancing overall activity of DNAzymes. We have shown that cationic copolymer enhanced DNAzyme activity by increasing turnover efficacy. In this paper, effects of the copolymer on DNAzymes modified with locked nucleic acids (LNA) or 2′-O-methylated (2′-OMe) nucleic acids were studied. The copolymer increased activity of these chemically modified DNAzymes. More than 30-fold enhancement in multiple-turnover catalytic activity was observed with 2′-OMe-modified DNAzyme in the presence of the copolymer. DNAzyme catalytic activity was successfully enhanced by cooperation of the added copolymer and chemical modification of DNAzyme.  相似文献   

14.
A new class of radiopaque copolymer using methyl methacrylate (MMA) and glycidyl methacrylate (GMA) monomers was synthesized and characterized. The copolymer was made radiopaque by the epoxide ring opening of GMA using the catalyst o-phenylenediamine and the subsequent covalent attachment of elemental iodine. The copolymer was characterized by Fourier transform infrared (FTIR) spectra, energy dispersive X-ray analysis using environmental scanning electron microscope (EDAX), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). X-ray visibility of the copolymer was checked by X-radiography. Blood compatibility and cytotoxicity of the newly synthesized copolymer were also evaluated. The iodinated copolymer was thermally stable, blood compatible, non-cytotoxic, and highly radiopaque. The presence of bulky iodine group created a new copolymer with modified properties for potential use in biomedical applications.  相似文献   

15.
采用自由基乳液聚合的方法制备带有环氧基团的聚丙烯酸全氟烷基乙酯-甲基丙烯酸缩水甘油酯-苯乙烯无规共聚物P(FA-co-GMA-co-St),用红外光谱(FT-IR)和核磁共振(1H-NMR)对共聚物进行表征并将其用于环氧涂料的改性。XPS测试结果表明,带有环氧基团的含氟共聚物改性环氧涂层经蒸馏水浸泡48 h后接触角下降了15°为116°,表面氟元素含量下降了5.36%;而不带有环氧基团共聚物改性环氧漆膜经水浸泡48 h以后接触角下降了48°为88°,表面氟元素含量下降了7.94%。GMA单体的引入极大地提高了环氧涂层在湿润环境中的疏水性。  相似文献   

16.
硅氧烷接枝改性丙烯酸树脂的合成及应用   总被引:3,自引:0,他引:3  
以多种丙烯酸酯类单体为原料合成羟基丙烯酸树脂,将硅酸乙酯部分水解缩聚制备聚硅氧烷,用硅氧烷对丙烯酸树脂接枝改性,制备出以丙烯酸树脂为主链、以具有水解特性及低表面能的有机硅为侧链的接枝共聚物,以此共聚物为基料,制备自抛光及低表面能复合型防污涂料.采用红外光谱、热重分析对接枝共聚物进行了表征,并测算了共聚物及制备的防污涂料涂膜的表面能.结果表明,合成的接枝共聚物与设计结构相符,其表面能达到23.63 mN/m,可用于防止海生物附着的防污涂料.  相似文献   

17.
在丙交酯与聚乙二醇开环共聚的基础上进行了二次聚合,利用具有生物相容性的赖氨酸对聚乳酸/聚乙二醇低聚物进行改性,制备出了赖氨酸改性聚乳酸/聚乙二醇共聚物。通过红外光谱、核磁共振谱、X射线衍射分析仪、差示扫描量热仪、凝胶渗透色谱和接触角测量仪分析比较了聚乳酸、聚乳酸/聚乙二醇和赖氨酸改性聚乳酸/聚乙二醇3种聚合物之间存在的差异。结果表明,实验成功合成了赖氨酸改性聚乳酸/聚乙二醇共聚物;赖氨酸(L-lys)的引入使得共聚物的热焓(ΔH)和熔点(T_m)分别由纯PLLA的81.57 J/g和177.34℃降到46.02 J/g和151.34℃,有效地改善了分子链的柔性和结晶度;聚合物的数均相对分子质量(M_n)也由纯PLLA的7.7×10~4降到了3.2×10~4,且相对分子质量分布变宽,但亲水性却得到大幅提高,有望适用于组织工程领域。  相似文献   

18.
氟碳丙烯酸酯对聚丙烯酰胺的改性   总被引:4,自引:0,他引:4  
用N-丙基,N-羟乙基全氟辛基磺酰胺(FC)与丙烯酸反应得到了N-丙基,N-羟乙基全氟辛基磺酰胺丙烯酸酯(FCA),再通过与丙烯酰胺共聚得了氟碳改性聚丙烯酰胺P(AM—FCA)。考察了共聚物中FCA单体含量、溶液温度、盐浓度、P(AM—FCA)质量分数对溶液粘度的影响.结果表明.在实验范围内.共聚物溶液的表现粘度随P(AM—FCA)质量分数和盐浓度的增加而增加,随溶液温度和FCA单体含量的增加出现极值,共聚物和聚丙烯酰胺相比,具有良好抗温、耐盐性能,可望作为三次采油用驱油荆。  相似文献   

19.
A synthetic route for the preparation of a novel solution copolymer derived from styrene (St), pyrrole (Py) and its organoclay nanocomposite with conductive and mechanical properties is demonstrated. The electroactive copolymer of polystyrene-g-polypyrrole (PSt-g-Ppy) nanocomposite was successfully prepared by atom transfer radical polymerisation (ATRP) and chemical polymerisation methods. First, potassium pyrrole was reacted by α-chlorophenyl acetyl chloride to prepare an initiator that can polymerise styrene by ATRP technique. Then, polypyrrole was prepared by chemical polymerisation using FeCl3 as an oxidant in dichloromethane,s solvent. Nanocomposites of the copolymer with modified montmorillonite were prepared with a solution intercalation method. The conductivity of the copolymer was measured by the four-point probe method. The structures of the intermediate, copolymer and nanocomposite were investigated by Fourier transform infrared spectroscopy, 1H-NMR and X-ray diffraction techniques. The molecular weight of the copolymer was determined by gel permeation chromatography. Their thermal behaviour was examined by differential scanning calorimetry and thermogravimetric analyses.  相似文献   

20.
《Thin solid films》2008,516(6):1197-1203
In this paper we present the characteristics of the Langmuir monolayers formed by amphotericin B 3-(N',N'-dimethylamino) propyl amide (AMA) that is a derivative of amphotericin B (AmB), a polyene antifungal antibiotic. Also, the interactions of AMA with sterols (cholesterol, ergosterol) and a phospholipid (l-α Phosphatidylcholine dipalmitoyl — DPPC) were studied in the mixed films. The experiments were based on measurements of the surface pressure during film compression and the results were analyzed with the isothermal compressibility, the excess area per molecule, the excess free energy of mixing and the total free energy of mixing values. It was found that the ionic state of AMA molecule affects its biological properties. Moreover, the size of the antibiotic molecule influences its interactions with sterols. Thus, AMA that is larger molecule than AmB reflects the higher selectivity as compared to the parent antibiotic. Interestingly, contrary to AmB derivatives investigated previously, the interactions between DPPC and AMA are not important from the point of view of biological properties of the antibiotic studied.  相似文献   

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