## 1 Introduction  
Electromagnetic interference (EMI) is a growing concern due to electromagnetic radiation pollution's economic losses and health risks. Electromagnetic interference (EMI) shielding materials are being developed to address this issue. Conductive polymer composites, such as carbon-based nanoparticles like CNTs, graphene, and CNFs, offer lightweight, low-cost, and corrosion-resistance advantages [1]. The shielding effectiveness of composites is influenced by the selection and loading of conductive nanoparticles, processing methods, and material structures, making it easy to prepare suitable materials for engineering or functional purposes [2, 3, 4, 5]. Electromagnetic absorbers are crucial in various fields, such as civil engineering, military electronics, and electromagnetic compatibility. They are essential for reducing radar visibility (stealth technology) in defense systems or minimizing interference from wind turbines on airport radar systems [6, 7, 8, 9]. Therefore, there is a pressing need to develop high-performance electromagnetic-absorbing materials (EMAMs) that offer high absorption rates, broad bandwidth absorption, lightweight construction, and low thickness. RADAR systems utilize centimeter-wavelength microwaves (3-30 GHz) for superior penetration and extended propagation, while millimeter-wavelength microwaves (30-300 GHz) are used in telecommunications and detection technologies. The centimeter-wave spectrum is primarily used for civil mobile communication, precise positioning systems, and satellite communications, while millimeter-wavelength microwaves are used in millimeter-wavelength microwaves [10; 11; 12]. EMI composite development often relies on experience and tedious experiments, making it inefficient and costly. Non-experimental methods like the coaxial transmission line method are used to predict the shielding effectiveness of carbon fiber reinforcements, laminated composites, and effective medium theories for composites with barium strontium titanate and/or nickel zinc ferrite inclusions. However, these numerical methods are computationally expensive and unsuitable for rapid prediction [13; 14; 15; 16; 17]. Carbon materials offer exceptional conductivity, a high specific surface area, and chemical stability, making them ideal for surface modification in microwave absorption. However, impedance mismatch can be mitigated by hybridizing with nanoparticles. Carbon nanotubes (CNTs) have also attracted significant attention due to their distinctive structural, mechanical, electrical, and thermal characteristics [18; 1; 19]. They are increasingly used as fillers to enhance the properties of polymers and develop advanced multifunctional composite materials. Polypropylene (PP) is a versatile and low-cost polymer with attractive properties but lacks specific engineering properties like mechanical strength and thermal characteristics. PP-carbon composites, incorporating CNTs/GNP, improve these properties while maintaining PP's lightweight and flexible nature [20; 21]. Research in EMAMs focuses on low-dimensionality, complexity, multifunctionality, and compatibility. Compatibility requires broadband absorbing characteristics, while complexity involves using composites of multiple materials for comprehensive performance. Combining various materials is crucial for well-rounded performance [3; 22; 23; 24]. The design of thin, lightweight, and lightweight absorbent materials with a broad bandwidth and good absorption performance is a common difficulty that arises throughout the optimization process. The absorption bandwidth and reflection loss are better with multi-layer coatings than with single-layer coatings because the material type and layer thickness can be changed [25; 26; 27; 28; 29; 30]. Optimization algorithms, including the genetic algorithm (GA), particle swarm optimization (PSO), and artificial bee colony (ABC) algorithm, have been implemented in the development of absorbent materials.