Towards anti-corrosion coatings from surfactant-free latexes based on maleic anhydride containing polymers

We report on the film formation of surfactant-free, artificial latexes based on copolymers containing maleic anhydride. Different metallic substrates, such as aluminum, steel and magnesium alloys, were coated with three different latexes. A commercial polyester based coating was used as a comparative sample. Two of the latexes were based on polymer with a high T_g (resp. 100 and 130 °C), and one on a polymer with a T_g of −70 °C. The wetting of the substrates could be optimized by etching the metal substrate, acidic or alkaline, leading to homogenous film formation and improved adhesion. For aluminum substrates an alkaline pretreatment improved the adhesion with the polymer films, whereas for magnesium the acidic pretreatment improved the adhesion. Furthermore, acid pretreatment increased the corrosion resistance of the coated magnesium substrate, when compared to an alkaline pretreatment. The films formed from latex displayed comparable or better anti-corrosive properties when compared to the commercial polyester.     

Use of styrene-maleic anhydride copolymers (SMA resins) in emulsion copolymerization

The composition and quantity of styrene-maleic anhydride (SMA) copolymer resins were varied in emulsion copolymerizations of methyl methacrylate and n-butyl acrylate conducted by both batch and semicontinuous processes. The resulting particle sizes and levels of coagulum were measured to determine the optimum conditions for incorporation of the SMA resins into the resulting latexes. A semicontinuous process, in which no buffer was included and the SMA was added in a second stage comonomer emulsion, was found to produce coagulum-free latexes. These recipes, however, relied on nucleation of the polymer particles by conventional surfactants [nonyl phenol poly(ethylene) oxide and its corresponding sulfate salt] with a first-stage addition of a monomer emulsion prepared with these surfactants. SMA1000, having a 1/1 ratio of styrene to maleic anhydride in its copolymer, was determined to be the preferred resin (as opposed to SMA2000 and SMA3000, having SMA ratios of 2/1 and 3/1, respectively) because it interacted the least with conventional surfactants, which allowed its ready incorporation into coagulum-free recipes. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2729–2747, 1998     

低温合成苯乙烯-马来酸酐交替共聚物

苯乙烯(St)和马来酸酐(MA)自由基引发共聚反应,生成共聚物SMA,是典型的交替共聚。在过氧化苯甲酰(BPO)引发下,以丙酮为溶剂,采用溶液聚合法合成苯乙烯-马来酸酐共聚物,并用收率作为评价标准,对反应条件进行研究。结果表明,在温度为60℃,BPO的质量分数x(BPO)=0.3%,n(苯乙烯)∶n(马来酸酐)=1∶1,w(单体)=30%,反应2 h的条件下,聚合物的收率可达到98.5%。利用化学滴定法测得聚合物中马来酸酐摩尔分数为49.91%,结合理论,证明了合成的苯乙烯-马来酸酐共聚物是一种交替共聚物。一种低温合成苯乙烯-马来酸酐交替共聚物的工艺得到开发。     

The comb-like modified styrene-maleic anhydride copolymer dispersant for disperse dyes

The comb-like styrene-maleic anhydride copolymer-g-isatoic anhydride-methoxypolyethylene glycols condensate (SMA-g-IA-MPEG) was synthesized by transesterification and amidation reaction. The chemical structure of SMA-g-IA-MPEG was characterized by FTIR and ¹H-NMR. The comb-like modified SMA was first employed as the dispersant of disperse dyes suspension in this paper. The addition of SMA-g-IA-MPEG dispersant improved the dispersibility and stability of the disperse dyes suspension observably due to the steric hindrance and electrostatic repulsion on the surface of dye particles. The impacts of the length of side chains on the particle size, Zeta potential, centrifugal stability, and temperature sensitivity of disperse dyes suspensions were particularly discussed. The results showed that SMA-g-IA-MPEG with moderate length of side chain had the best dispersibility for disperse dyes suspension and the average particle size of dyes can be reduced to 356.1 nm. Thus, the comb-like dispersants played a vital role in dispersing of disperse dyes. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47330.     

Phase behaviour of ternary system styrene-maleic anhydride (SMA) and two styrene-acrylonitrile (SAN) copolymers having different compositions

The phase behaviour of the binary copolymer systems SMA-SAN and SAN-SAN can be described well using the copolymer repulsion model. However, the phase behaviour of the ternary system consisting of SMA-SAN(1)-SAN(2) with SAN(1) and SAN(2) having different chemical compositions is not known. In order to reveal this, the composition of the blends, the composition of the SMA (ranging from 22 to 34 wt% MA) at constant SAN compositions (26, 34 and 28, 32 wt% AN), the molar mass of the SMA (M_w=3.5 and 110 kg/mol) as well as the temperature (25 and 230°C) were varied. The number of phases was studied using differential scanning calorimetry (DSC) and a critical evaluation of the predicted and observed glass transition temperatures based on the Fox equation. The binodals and spinodals were calculated using the Flory-Huggins approach. From a comparison of predicted and observed miscibility, it is concluded that this ternary system can be described using the aforementioned model.     

SMA的合成及其对香精的分散和微胶囊制备的影响

使用溶液聚合法合成苯乙烯-马来酸酐共聚物（SMA）,利用盐化的苯乙烯-马来酸钠盐作为保护胶体分散香精,采用原位聚合法制备三聚氰胺甲醛树脂香精油微胶囊。探究了不同分子量的SMA钠盐对香精的分散作用和对香精油微胶囊制备的影响,并与进口SMA 520对香精的分散作用和微胶囊制备效果进行了对比。实验发现,随着SMA分子量减小,香精油趋向于以较小粒径的液滴分散在连续相中,粒径分布逐渐变窄,香精油滴的分散稳定性提高。当使用的SMA钠盐溶液（质量分数10%）黏度≥145mPa·s时,可制备出粒径为5～20μm,形态为球形、表面有少许凹陷、壳层厚度较为均匀的微胶囊。当使用的SMA钠盐溶液（质量分数10%）的黏度≤67mPa·s时,只能形成极少数的球形微胶囊。作为保护胶体制备香精油微胶囊,进口SMA 520与实验室制备的黏度为314mPa·s的SMA钠盐溶液（质量分数10%）具备相似的效果。     

PDMS-modified poly(styrene-alt-maleic anhydride)s as water-borne coatings based on surfactant-free latexes

In this work, two series of PDMS-modified poly(styrene-alt-maleic anhydride)s (PSMA) were prepared by the partial imidization of their anhydride groups with mono-functional, amine-terminated polydimethyl siloxanes (PDMS-NH₂) with two different molecular weights. Subsequently, surfactant-free artificial latexes were prepared and characterized and applied onto cotton fabric. The water contact angle values of the coated cotton fabric indicate the formation of hydrophobic surfaces, with static contact angles varying from 119° to 142° depending on the PDMS loading and PDMS molecular weight. Coatings of the prepared copolymers on cotton fabric are highly durable, as shown by washing studies with a standard soap solution. The properties of these water-based surfactant-free latexes can be tuned easily by changing the composition of the polymers, i.e. mol% of imidization, ammonolysis and cross-linking.     

Hydrogenation of styrene-butadiene rubber (SBR) latexes

The mechanism and the optimum conditions for the reduction of residual double bonds in styrene-butadiene rubber (SBR) latex by hydrogenating the polybutadiene in the latex form were studied. The hydrogenation involves a copper ion (II)-catalyzed procedure in which diimide hydrogenation agent is generated in situ at the surfaces of latex particles by a hydrazine/hydrogen peroxide redox system. The surface density of the copper ion in particle surfaces was found to be a crucially important parameter in controlling the degree of hydrogenation. The distribution of the double bonds in the latex particles after the hydrogenation was found to be dependent on the particle size and the extent of crosslinking in the particles. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2047–2056, 1997     

Grafting behavior of n-butyl acrylate onto poly(butadiene-co-styrene) latexes

The radical-induced grafting of n-butyl acrylate (BA) onto poly(butadiene-co-styrene) [(P(Bd-S)] latexes during seeded emulsion polymerization was studied. This P(Bd-S)/PBA rubber/rubber core/shell latex system exhibited unique grafting behavior as compared to other extensively studied rubber/glass core/shell latex systems, such as poly(butadiene-co-styrene)/poly(methyl methacrylate) [P(Bd-S)/PMMA], poly(butadiene-co-styrene)/polystyrene [P(Bd-S)/PS] and poly(butadiene-co-styrene)/poly(acrylonitrile)[P(Bd-S)/PAN]. These composite latexes were characterized by the formation of a highly grafted/crosslinked P(Bd-S)/PBA interphase zone generated during the seeded emulsion polymerization process. Although both of the individual core and shell polymers studied were “soft” themselves, the resulting P(Bd-S)/PBA composite latex particles were found to be rather “hard.” The formation of the interphase zone was studied by using techniques such as solvent extraction, differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:511–523, 1997     

In situ compatibilization of polystyrene and polyurethane blends by using poly(styrene-co-maleic anhydride) as reactive compatibilizer

Blends of polystyrene (PS) and polyurethane (PU) elastomer were obtained by melt mixing, using poly(styrene-co-maleic anhydride) (SMA) containing 7 wt % of maleic anhydride groups as a reactive compatibilizer. Polyurethanes containing polyester flexible segments, PU-es, and polyether flexible segments, PU-et, were used. These polyurethanes were crosslinked with dicumyl peroxide or sulfur to improve their mechanical properties. The anhydride groups of SMA can react with the PU groups and form an in situ graft copolymer at the interface of the blends during their preparation. The rheological behavior was accompanied by torque versus time curves and an increase in the torque during the melt mixing was observed for all the reactive blends, indicating the occurrence of a reaction. Solubility tests, gel permeation chromatography, and scanning electronic microscopy confirmed the formation of a graft copolymer generated in situ during the melt blending. These results also indicate that this graft copolymer contains C C bond between SMA and PU chains. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2514–2524, 2001     

Functional polymers for colloidal applications (III): Structural effects of lipophile-modified styrene-maleic anhydride copolymers on dispersing polar and nonpolar particles

Styrene-maleic anhydride copolymer (SMA) with the molecular weight (MW: 7100) suitable for acting as a dispersant was synthesized and then ring-opened with alkylamine to prepare the n-butyl and n-dodecyl-substituted SMA. The prepared lipophile-modified SMA copolymers were used as dispersants to disperse both polar and nonpolar particles (TiO₂ and carbon black). Upon dispersing TiO₂ and carbon black, the antibridging effect (a larger optimum concentration and a less sharp increase after optimum concentration) was observed for SMA as well as n-butylamide-substituted SMA as compared to sodium polyacrylate. The bridging effect, however, is obvious for n-dodecylamide highly substituted SMA (12N45). For dispersing TiO₂, both for n-butyl and n-dodecylamide-substituted SMA, the curve of viscosity vs. concentration increases less sharply after optimum concentration except for 12N45. In the case of dispersing carbon black, the n-butylamide-substituted SMA shows a pronounced antibridging effect, while the n-dodecylamide-substituted SMA shows a significant bridging effect. The minimum viscosity and the optimum concentration for both n-butyl and n-dodecylamide-substituted SMA are correlated to conclude that: (a) at low percentage of alkylamide in SMA, both for n-butyl and n-dodecyl group cause bridging phenomena and increase the viscosity; (b) as the percentage of alkylamide in SMA increase, the adsorption effect is more important for n-butylamide-substituted SMA (e.g., 4N45), and the bridging effect is more important for n-dodecylamide-substituted SMA (e.g., 12N45); (c) the decrease in optimum concentration for 12N45 can be interpreted by the bridging effect.     

Hole structure and its formation in thin films of hydrolyzed poly(styrene maleic anhydride) alternating copolymers

Maleic anhydride moieties on the backbone chains of poly(styrene maleic anhydride) alternating copolymer (SMA) hydrolyzed in a THF solution containing water and hydrochloric acid. Well‐arrayed holes were obtained in spin‐cast thin hydrolyzed SMA films on a single crystal silicon wafer, and the hole diameter and its distribution were measured with AFM data. Results showed that the hole size was almost uniform, and was influenced by water content when spin speed was kept unchanged. The THF solution with a SMA concentration of about 1 g/mL and weight ratio H₂O/SMA of 1/3 produced holes having an average diameter of 0.60 μm and depth of 206.12 nm, when cast at a spin speed of 1400 rpm. It was noted that the formation of the holes in thin hydrolyzed SMA film was different from the dewetting process in thin homopolymer films, but was associated with the intrinsic properties of the copolymer forming the films. The surfactant effect of hydrolyzed SMA was suggested to interpret the formation of the holes. The holes were described to be the traces of water droplets that were emulsified by the hydrolyzed SMA during casting. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 267–274, 2000     

Insights in the molecular structure of low- and high-molecular weight poly(styrene-maleic anhydride) from vibrational and resonance spectroscopy

Poly(styrene-maleic anhydride) or SMA are versatile copolymers available in different grades of molecular weight (M_w = 5500–170,000 g/mol) and molar percentage of maleic anhydride (22–50 mol-%). As specific grades can be used for the synthesis of nanoscale structures in paper industry, a better understanding of the molecular structure was needed. Therefore, a broad range of SMA grades was analyzed by means of size exclusion chromatography, infrared spectroscopy, Raman spectroscopy and nuclear magnetic resonance spectroscopy. While the nominal composition could be determined by ¹H NMR and Raman spectroscopy, the combination with ¹³C NMR and FTIR allowed a more detailed characterization of the molecular structure. The high-molecular weight SMA grades show a heterogeneous molecular structure with segments including high styrene and maleic anhydride moieties, respectively. The formation of film patterns was evaluated by deposition from an acetone solution, resulting in homogeneous films, fibrous structures, or spherical shapes with decreasing diameter as a function of maleic anhydride content including primary particle sizes of 100 nm. This study illustrates intrinsic molecular features of SMA grades that are capable for self-assembly, and can provide a selection tool for future nanoparticle formulation.     

醋酸乙烯酯-丙烯酸丁酯共聚乳液地板胶的研制

用醋酸乙烯酯与丙烯酸丁酯进行乳液共聚合,所得产物用作木地板胶粘剂。介绍了它的合成方法和性能,讨论了粘接试件浸水24小时后的不同自然干燥时间、胶层厚度等对剪切强度的影响。     

Electrochemical impedance spectroscopy (EIS) study of nano-alumina modified alkyd based waterborne coatings

A nano-composite coating was formed by dispersing nano-Al₂O₃ as pigments in different concentrations, to a specially developed alkyd based waterborne coating. The nano-Al₂O₃ based composite coatings were applied on mild steel substrate by dipping. The dispersion of particles in coating system was investigated by using SEM and AFM techniques. The effect of addition of these nano-pigments on the electrochemical behavior of the coating was investigated in 3.5% NaCl solution, using electrochemical impedance spectroscopy (EIS). It was found that coating modified with higher concentration of nano-Al₂O₃ particles showed comparatively better performance as it was evident from pore resistance (R_p) and coating capacitance (C_c) values after 30 days of exposure. In general, the study showed an improvement in the corrosion resistance of the nano-particle modified coatings as compared to the neat coating, confirming the positive effect of nano-particle addition in coatings.     

苯乙烯-马来酸酐树脂在覆铜箔板中的应用

探讨了苯乙烯 -马来酸酐树脂 (SMA)固化改性普通溴化环氧树脂在覆铜箔板中的应用工艺和主要性能 ,结果表明改性后的覆铜箔板的一些主要性能指标基本达到普通FR - 4要求 ,不但能够显著提高基材的耐热性 ,并且大幅度降低了基材的介电常数和介质损耗 ,表现出优秀的介电性能 ,可望在高频通讯基板领域中获得重要应用     

Electrospinning of poly(styrene-co-maleic anhydride) (SMA) and water-swelling behavior of crosslinked/hydrolyzed SMA hydrogel nanofibers

Random and alternating poly(styrene-co-maleic anhydrides) (SMAs) with respective maleic anhydride (MAh) content of 32 and 48% were synthesized through radical polymerization. SMA nanofibers with diameter down to 180 nm were generated by electrospinning from solvents acetone, dimethylformamide (DMF), and their mixtures. Fiber diameter increased dramatically when the SMA concentration in the spinning solution reached to a critical point where the SMA chains are extensively entangled. The diameter of SMA nanofiber decreased with increasing DMF content in the mixture, but beads are often accompanied as DMF content is over 50%. The optimum acetone/DMF ratio was found to be 2:1, in which continuous electrospinning was achieved and bead-free nanofibers were obtained. SMA nanofibers with MAh content of 32 and 48% were crosslinked with diethyleneglycol and subsequently hydrolyzed in NaOH/EtOH to turn SMA into crosslinked sodium form SMA (SMA-Na) hydrogel nanofiber. These hydrogel nanofibers were able to retain fiber form after immersing in water for 24 h. Their water absorption ratio was up to 37.6 and 8.2 g/g in distilled water and 0.25 N NaCl aq. solution, respectively.     

苯乙烯马来酸酐共聚物（SMA）化学改性制备荧光聚合物及其荧光性能研究

用自行合成的2－氨基噻唑（1），2－氨基－4－苯基噻唑（2），2－氨基苯并噻唑（3）等荧光小分子化合物，与商品化的苯乙烯马来酸酐共聚物（SMA）中的酸酐基团反应，制成聚苯乙烯马来酰亚胺（SMI），实现了SMA化学改性，在获得荧光聚合物的同时，不仅保持了原SMA的可溶性，成膜性等优点，其热性能也得到了改善，通过示差扫描量热（DSC），凝胶色谱（GPC），红外，紫外及荧光光谱等手段表征了荧光聚合物的玻璃化转变温度，分子量及结构与荧光性能关系。     

Studies on poly(styrene‐co‐maleic anhydride)‐modified polyesteramide‐based anticorrosive coatings synthesized from a sustainable resource

Polyesteramide (PEA) coating resin, synthesized from linseed oil, a sustainable resource, was found to show improved physicomechanical and acid‐resistance properties. To further improve these properties in terms of alkali resistance, scratch hardness, and thermal stability and to reduce the baking temperature, we have attempted to incorporate styrene into the polymer backbone through its copolymer with maleic anhydride. The structural elucidation of modified PEA resin (SCPEA) was carried out by FTIR, ¹H‐NMR, and ¹³C‐NMR spectroscopes. The physicomechanical and chemical‐resistance properties were investigated by standard methods and thermal stability was investigated by thermogravimetric analysis method. A comparative study of these properties of PEA and SCPEA was carried out. It was observed that the SCPEA showed better properties than the reported one. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2538–2544, 2004     

聚(丁二酸丁二酯-co-衣康酸丁二酯)的合成

用含不饱和双键基团的衣康酸作共聚单体,采用直接熔融酯化聚合法制备可生物降解的聚(丁二酸丁二酯-co-衣康酸丁二酯)。共聚物的相对分子质量及其分布、溶解性能、热性能及结晶性能均受分子链中衣康酸含量的影响,当衣康酸摩尔分数达50%时,共聚物成为不溶/熔的交联弹性体。