Global Analysis of Polyfluorene via AB-Type Suzuki–Miyaura Polymerization: Empirical and Mechanistic Rationalization of Structural and Reaction Parameters on Molar Mass, Dispersity, and Yield

The preparation of conjugated polymers with precisely
tunable optoelectronic
properties is based on modern polymerization techniques. In addition
to conventional step-growth polycondensation for the underlying C–C
coupling steps, the Suzuki-Miyaura catalyst-transfer polymerization
(SCTP) continues to attract great interest, as it enables chain growth
with controlled molar masses, dispersity values, and end group fidelity.
The combination of these beneficial properties allows for use in defined
block copolymers or as functional building blocks in functional polymer
architectures aiming to control energy and charge transfer at the
macromolecular level. For an ideal SCTP mechanism, a ring-walking
step is crucialand many experimental parameters contribute
to the overall success of the polymerization to tailor the desired
degree of polymerization, low dispersity values, and high yields.
Many reports explored specific combinations within the available parameter
space, yet a unifying analysis to identify limitations as well as
promising future directions to advance synthetic methodologies is
needed. In this work, all available experimental data for the AB-type
2,7-linked poly(fluorene) is collected, and a detailed algorithmic
global analysis is presented, including the tabulated results for
machine learning and reinspection of the collected raw data. It is
found that SCTP is typically obeyed for monomer-to-catalyst ratios
up to 25, while the combination of tBu3P-based Pd precatalysts and boronate-based monomers enables
excellent SCTP fidelity with monomer-to-catalyst ratios up to 500.

制备具有精准可调光电性能的共轭聚合物，需依托现代聚合技术实现。除用于核心碳-碳偶联步骤的传统逐步缩聚法外，铃木-宫村催化剂转移聚合（Suzuki-Miyaura catalyst-transfer polymerization, SCTP）始终备受关注，因其可实现摩尔质量、分散度与端基保真度均可控的链增长过程。上述优势特性的组合，使该聚合方法可应用于定制化嵌段共聚物的制备，或是作为功能聚合物架构中的功能构筑基元，以期在大分子层面实现对能量与电荷转移过程的精准调控。对于理想的铃木-宫村催化剂转移聚合机理而言，环行走步骤至关重要——诸多实验参数共同影响聚合反应的整体效果，以实现目标聚合度、低分散度及高收率的调控。现有诸多研究已探索了参数空间内的特定组合，但仍需开展统一性分析以明确其局限性，并为合成方法的进阶发展指明富有前景的方向。本研究收集了所有针对AB型2,7-连接聚芴的实验数据，并呈现了详细的算法全局分析，包括机器学习所得制表结果以及对收集到的原始数据的重新检视。研究发现，当单体与催化剂比例不超过25时，反应通常符合铃木-宫村催化剂转移聚合机理；而基于三叔丁基膦（tBu3P）的钯预催化剂与硼酸酯类单体的组合，可实现优异的铃木-宫村催化剂转移聚合保真度，此时单体与催化剂比例最高可达500。