Analysis of Terpolymerization Systems for the Development of Carbon Fiber Precursors of PAN

Abstract

The thermal stabilization of polyacrylonitrile fibers (FPAN) is one of the most important steps in the production of carbon fibers (CFs). In this paper, new precursor polymers from PAN have been synthesized with different chemical characteristics using a solution polymerization, and FPAN was obtained using an unconventional wet spinning system in the drying and collapsing steps. The effect of different operation conditions, comonomers, and termonomers on the properties of precursor polymers, polymerization reactions, mechanical properties, structural characteristics, and stabilization of the FPAN was studied and analyzed. FTIR and optical microscopy were used to analyze structural changes of FPAN in the thermal stabilization. The impact of the chemical composition of the precursor polymers on the physicochemical characteristics of FPAN and their behavior in the thermal stabilization process were evaluated. In particular, itaconic acid termonomer improved the tensile strength of the fibers from 8.07 to 16.87 cN/dtex, and the extent stabilization increased from 1.81 to 4.6. FTIR indicated that the reaction of stabilization of the terpolymer developed was initiated at a lower temperature compared to that of a commercial precursor polymer.

Fiber Formation of Printed Carbon Fiber/Poly (Ether Ether Ketone) with Different Nozzle Shapes

“…Instead, the profile is bean‐shaped. This fiber cross‐section can result from the manufacturing process 55,56 . To obtain an estimate of the frequency of non‐circular fiber cross‐sections, a phase analysis is performed.…”

Designing Materials and Processes for Strong Polyacrylonitrile Precursor Fibers

“…Such a copolymer also affects the mechanical properties, and the properties of the fiber vary depending on the copolymer composition under the same spinning conditions. For example, there was a study reporting a PAN-MA-IA terpolymer with doubled strength (16.87 cN/dtex) of the commercial-grade copolymer (PAN-MA (90 wt% AN and 10 wt% MA)) [ 48 ]. Thus, it is important to optimize the comonomer content to achieve strong carbon fiber properties by satisfying multiple aspects: good spinnability, high crystallinity, and optimum thermal transformable structure.…”

Reversible addition–fragmentation chain transferbased copolymers of acrylonitrile and alkyl acrylates as possible precursors for carbon fibers: synthesis and thermal behavior during stabilization

“…Alkyl acrylates belong to the former type of monomers while acidic and amidic monomers belong to the latter type. [9][10][11][12][13][14][15][16][17][18][19][20] The commercial PAN-based copolymers typically include binary copolymers of AN and methyl acrylate (MA) or their ternary copolymers with acrylic or itaconic acids. 1,2 MA is the most studied among the acrylate monomers used for the production of PAN-based precursors.…”

“…The comonomers that are typically used to eliminate the above‐mentioned shortcomings act either as an inert additive which increases the chain flexibility, disorders the crystalline structure and enhances processability of the fiber or as an accelerator of the cyclization reaction which shifts the reaction to the low‐temperature range and decreases the intensity of its heat release. Alkyl acrylates belong to the former type of monomers while acidic and amidic monomers belong to the latter type 9–20 . The commercial PAN‐based copolymers typically include binary copolymers of AN and methyl acrylate (MA) or their ternary copolymers with acrylic or itaconic acids 1,2 …”