**2. Experimental**

for hard-materials applications [2]. Substantial improvements in hardness, wear resistance, oxidation resistance, resistance to chemicals, and electrical conductivity are the main charac‐ teristics attainedbypolymericmaterials aftertheirlow-to-medium-energyionimplantation[3–

particular, the ion irradiation of polymers leads to the scission and cross-linking of polymer chains, formation of volatile low-molecular fragments, and carbonization of the implanted layer. The carbonization process depends strongly on the implantation dose or/ and ion current density. As ion dose increases, the several stages can be distinguished for carbonization to be occurred. The formation of pre-carbon structures, nucleation, and growth of the carbonenriched clusters, aggregation of the clusters, formation of network of conjugated bonds, and transition to amorphous carbon or graphite-like material are the main stages predicted in literature [8–10]. Despite numerical studies of carbonization processes in polymers, the problem remains to understand better how the carbonaceous phase or carbon nanostructures formed under high-dose ion implantation could be dependent on the type of polymer matrix.

into various polymer matrix such as polycarbonate, Kapton, polyethylene, polyamide, polyimide, poly(ethylene terephthalate), cellulose, polypropylene, polystyrene, polyethersul‐

tation into widely used in practice polymer polymethylmethacrylate (PMMA) was not studied

matrix results in significant increase of surface-sensitive mechanical properties. So, Lee et al. [4] reported the ion-induced improvement in hardness of Kapton irradiated by three different

largest improvement in hardness among the three, not following the increasing trend in atomic

this polymer for construction of many optical components (waveguides, lenses, prisms, etc.), lithography, biomedical applications, etc. ([26–30] and references therein). PMMA was also a

[29, 30] that may find an extensive application in fabrication of various optoelectronic devices including organic light-emitting diodes, backlight components in liquid crystal display systems, diffractive elements, solar cells, waveguides, microcomponents for integrated optical circuits, etc. The well-known key performance and important characteristics of PMMA such as a long-term stability in outdoor environments, excellent surface hardness, light weight, outstanding transmittance and optical clarity, optical design flexibility and control, etc. [32], and high stability upon positron irradiation at room temperature [33] are also taken into


) in the most polymeric materials are of general concept [8–10]. In

) and carbonization at higher





, where boron produced the

, N+

and Ar+



The formation of free radicals at lower ion doses (<1016 ions/cm2

In this respect, a lot of efforts have been made by researchers studying the B+

layer leading to increasing conductivity [20, 23]. Also, B+

The selection of PMMA matrix to be used for B+

subject for implantation with Ag+

ion species, He, B, and Si at 200 keV to a dose of 3.5 × 1019 ions/m2

nanoparticles for plasmonic applications as well as for implantation with C+

account at the selection of basic polymeric matrix for low-energy ion implantation.

fone, and others ([2, 4, 5, 11–25] and references therein). At the same time, the B+

7].

so far.

number.

The interest to B+

ion doses (>1016 ions/cm2

288 Radiation Effects in Materials
