Epping Ruben, Panne Ulrich, Hiller Wolf, Gruendling Till, Staal Bastiaan, Lang Christiane, Lamprou Alexandros, Falkenhagen Jana
Bundesanstalt für Materialforschung und -prüfung (BAM) Berlin Germany.
Chemistry Department Humboldt Universität zu Berlin Berlin Germany.
Anal Sci Adv. 2020 Jun 5;1(1):34-45. doi: 10.1002/ansa.202000044. eCollection 2020 Jun.
Copolymer products that result from grafting acrylic acid and other hydrophilic monomers onto polysaccharides have recently gained significant interest in research and industry. Originating from renewable sources, these biodegradable, low toxicity, and polar copolymer products exhibit potential to replace polymers from fossil sources in several applications and industries. The methods usually employed to characterize these copolymers are, however, quite limited, especially for the measurement of bulk properties. With more sophisticated applications, for example, in pharmaceutics requiring a more detailed analysis of the chemical structure, we describe a new approach for this kind of complex polymers. Our approach utilizes chromatography in combination with several detection methods to separate and characterize reaction products of the copolymerization of acrylic acid and chemically hydrolyzed starch. These samples consisted of a mixture of homopolymer poly (acrylic acid), homopolymer hydrolyzed starch, and - in a lower amount - the formed copolymers. Several chromatographic methods exist that are capable of characterizing either poly (acrylic acid) or hydrolyzed starch. In contrast, our approach offers simultaneous characterization of both polymers. The combination of LC and UV/RI offered insight into the composition and copolymer content of the samples. Size exclusion chromatography experiments revealed the molar mass distribution of homopolymers and copolymers. FTIR investigations confirmed the formation of copolymers while ESI-MS gave more details on the end groups of hydrolyzed starches and poly (acrylic acids). Evidence of copolymer structures was obtained through NMR measurements. Finally, two-dimensional chromatography led to the separation of the copolymers from both homopolymers as well as the additional separation of sodium clusters. The methods described in this work are a powerful toolset to characterize copolymerization products of hydrolyzed starch and poly(acrylic acid). Together, our approach successfully correlates the physicochemical properties of such complex mixtures with their actual composition.
通过将丙烯酸和其他亲水性单体接枝到多糖上而得到的共聚物产品最近在研究和工业领域引起了广泛关注。这些源自可再生资源的可生物降解、低毒性且具有极性的共聚物产品在多个应用和行业中展现出替代化石源聚合物的潜力。然而，通常用于表征这些共聚物的方法相当有限，尤其是在测量本体性能方面。例如，在需要对化学结构进行更详细分析的制药等更复杂的应用中，我们描述了一种针对这类复杂聚合物的新方法。我们的方法利用色谱法结合多种检测方法来分离和表征丙烯酸与化学水解淀粉共聚反应的产物。这些样品由均聚物聚丙烯酸、均聚物水解淀粉以及少量形成的共聚物组成。存在几种能够表征聚丙烯酸或水解淀粉的色谱方法。相比之下，我们的方法能够同时表征这两种聚合物。液相色谱（LC）和紫外/示差折光检测（UV/RI）的结合提供了有关样品组成和共聚物含量的信息。尺寸排阻色谱实验揭示了均聚物和共聚物的摩尔质量分布。傅里叶变换红外光谱（FTIR）研究证实了共聚物的形成，而电喷雾电离质谱（ESI-MS）则提供了有关水解淀粉和聚丙烯酸端基的更多细节。通过核磁共振（NMR）测量获得了共聚物结构的证据。最后，二维色谱实现了共聚物与两种均聚物的分离以及钠簇的进一步分离。本文所述的方法是表征水解淀粉和聚丙烯酸共聚产物的强大工具集。总之，我们的方法成功地将此类复杂混合物的物理化学性质与其实际组成联系起来。
