Mısır Murat
Faculty of Engineering and Architecture, Kırşehir Ahi Evran University, 40100 Kırşehir, Türkiye.
Polymers (Basel). 2025 Mar 25;17(7):873. doi: 10.3390/polym17070873.
In this study, novel triblock copolymers, including poly(-isopropylacrylamide)--poly(-caprolactone)--poly(-isopropylacrylamide) (PNIPAM--PCL--PNIPAM), poly(-vinyl-pyrrolidone)-block-poly(-caprolactone)-block-poly(-vinyl-pyrrolidone) (PNVP--PCL--PNVP), poly(-isopropylacrylamide--,-dimethylaminoethyl methacrylate)--poly(-caprolactone)--poly(-isopropylacrylamide--,-dimethylaminoethyl methacrylate) (P(DMAEMA--NIPAM)--PCL--P(NIPAM--DMAEMA)), and poly(,-dimethylacrylamide)--poly(-caprolactone)--poly(,-dimethylacrylamide) (PDMA--PCL--PDMA), were synthesized via a combination of ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. The synthesis was performed using novel bifunctional PCL-based RAFT macro chain transfer agents (macroCTAs; MXTPCL-X1 and MXTPCL-X2) with a -xylene-bis(2-mercaptoethyloxy) core. Initially, -xylene-bis(1-hydroxy-3-thia-propane) (MXTOH), which has not previously been used in lactone polymerization, was synthesized via the reaction of ,'-dibromo--xylene with 2-mercaptoethanol in the presence of sodium in ethanol. Subsequently, Sn(Oct)-catalyzed ROP of -caprolactone (-CL) using MXTOH as an initiator yielded PCL-diol (MXTPCLOH). The resulting PCL-diol underwent further functionalization through esterification and substitution reactions, leading to the formation of PCL-based RAFT macroCTAs. Triblock copolymers were synthesized using these macroCTAs with AIBN as an initiator. The synthesized products, along with their intermediates, were characterized using FTIR and H NMR spectroscopy. The number average molecular weight (M) and polydispersity index () of PCL-based macroCTAs were determined by using GPC analysis. The sensor capabilities of the synthesized novel triblock copolymers were investigated on the determination of syringic acid and it was determined that the most sensitive polymer was PNVP--PCL--PNVP (MXTP2). The working range was between 1.5 µg/mL and 15 µg/mL and the limit of detection (LOD) was found to be 0.44 µg/mL using DPV on MXTP2 polymer sensor.
在本研究中，通过开环聚合（ROP）和可逆加成-断裂链转移（RAFT）聚合相结合的方法合成了新型三嵌段共聚物，包括聚（N-异丙基丙烯酰胺）-聚（ε-己内酯）-聚（N-异丙基丙烯酰胺）（PNIPAM-PCL-PNIPAM）、聚（N-乙烯基吡咯烷酮）-嵌段-聚（ε-己内酯）-嵌段-聚（N-乙烯基吡咯烷酮）（PNVP-PCL-PNVP）、聚（N-异丙基丙烯酰胺-co-N,N-二甲基氨基乙基甲基丙烯酸酯）-聚（ε-己内酯）-聚（N-异丙基丙烯酰胺-co-N,N-二甲基氨基乙基甲基丙烯酸酯）（P（DMAEMA-NIPAM）-PCL-P（NIPAM-DMAEMA））和聚（N,N-二甲基丙烯酰胺）-聚（ε-己内酯）-聚（N,N-二甲基丙烯酰胺）（PDMA-PCL-PDMA）。合成过程使用了以对二甲苯双（2-巯基乙氧基）为核的新型双功能基于PCL的RAFT大分子链转移剂（大分子CTA；MXTPCL-X1和MXTPCL-X2）。首先，通过在乙醇中钠的存在下，使对二溴对二甲苯与2-巯基乙醇反应，合成了此前未用于内酯聚合的对二甲苯双（1-羟基-3-硫杂丙烷）（MXTOH）。随后，以MXTOH为引发剂，在Sn（Oct）₂催化下进行ε-己内酯（ε-CL）的ROP反应，得到PCL二醇（MXTPCLOH）。所得的PCL二醇通过酯化和取代反应进一步功能化，从而形成基于PCL的RAFT大分子CTA。使用这些大分子CTA并以偶氮二异丁腈（AIBN）为引发剂合成了三嵌段共聚物。使用傅里叶变换红外光谱（FTIR）和氢核磁共振光谱（¹H NMR）对合成产物及其中间体进行了表征。通过凝胶渗透色谱（GPC）分析测定了基于PCL的大分子CTA的数均分子量（Mₙ）和多分散指数（Đ）。研究了合成的新型三嵌段共聚物对丁香酸的传感能力，确定最敏感的聚合物是PNVP-PCL-PNVP（MXTP2）。在MXTP2聚合物传感器上使用差分脉冲伏安法（DPV）测定，其工作范围在1.5 μg/mL至15 μg/mL之间，检测限（LOD）为0.44 μg/mL。
