The Reversible Addition Fragmentation chain Transfer (RAFT) polymerizations of acrylic acid were performed in 1,4-Dioxane solution using three different chain transfer agent (CTA), and 4,4′-azobis(4-cyanopentanoic acid) (ACPA) as initiator. The molar ratios of monomer, CTA and initiator were kept similar for each experiment and all polymerization exhibited high conversion (>90%) at 8 h. Well-defined polyacrylic acids (PAAs) were obtained. Their molecular weights increased linearly with monomer conversion and the dispersity of the molecular weight distribution extended between 1.1 and 1.3. Nuclear magnetic resonance (NMR) spectroscopic studies showed that the PAA prepared are actually random copolymers of AA and the dimer of AA (H₂C=CHCO₂CH₂CH₂CO₂H), which forms spontaneously from AA, even at room temperature. PAA samples were methylated by addition of trimethylsilyldiazomethane (TMSCHN₂ a methylating agent) using a mixture of water/tetrahydrofuran (THF) or methanol/THF. Samples were submitted to different analyses before and after the methylation process in the order to examine the effect of the methylating agent. PAA were characterized by size exclusion chromatography (SEC) in aqueous phase and also in organic phase following methylation. Methylation is accompanied by variable amounts of chain cleavage in the case of PAA prepared using a symmetrical, trithiocarbonate RAFT chain transfer agent. Less extensive cleavage is seen on treatment of poly(methyl acrylate) (PMA), prepared from the trithiocarbonate RAFT reagent with TMSCHN₂. Fourier transform infrared (FT-IR), UV-Vis, 1D and 2D NMR spectroscopic studies confirmed that TMSCHN₂ reacts with the thiocarbonyl group, though all of the products of this reaction could not be identified. End group analysis using Ellman's reagent demonstrates that some of the polymer chains have a thiol end group, as does a thiol-ene reaction using 9-vinylcarbazole.

丙烯酸的可逆加成断裂链转移（RAFT）聚合反应是在1,4-二恶烷溶液中使用三种不同的链转移剂（CTA）和4,4'-偶氮双（4-氰基戊酸）（ACPA）作为引发剂进行的。在每个实验中，单体，CTA和引发剂的摩尔比保持相似，并且所有聚合反应在8小时内均显示出高转化率（> 90％）。获得了明确的聚丙烯酸（PAA）。它们的分子量随单体转化率线性增加，分子量分布的分散性在1.1和1.3之间扩展。核磁共振（NMR）光谱研究表明，制备的PAA实际上是AA和AA二聚体的无规共聚物（H ₂ C = CHCO ₂ CH ₂ CH ₂CO ₂ H），即使在室温下也能自发形成AA。通过添加三甲基甲硅烷基重氮甲烷（TMSCHN ₂（甲基化剂），使用水/四氢呋喃（THF）或甲醇/ THF的混合物。为了检查甲基化剂的作用，在甲基化过程之前和之后将样品进行不同的分析。PAA的特征是在甲基化后的水相和有机相中进行尺寸排阻色谱（SEC）。在使用对称的三硫代碳酸酯RAFT链转移剂制备的PAA的情况下，甲基化伴随着可变数量的链断裂。在用TMSCHN _2处理由三硫代碳酸酯RAFT试剂制备的聚（丙烯酸甲酯）（PMA）时，发现裂解程度较低。傅里叶变换红外（FT-IR），UV-Vis，1D和2D NMR光谱研究证实了TMSCHN ₂与硫代羰基反应，尽管无法确定该反应的所有产物。使用Ellman试剂进行的端基分析表明，某些聚合物链具有巯基端基，使用9-乙烯基咔唑的巯基-烯反应也是如此。