Strategy for Securing Key Patents in the Field of Biomaterials Abstract The quality of life is gradually improving with the development of medicine and the rising standard of living, but human beings are still faced with the risks of various diseases, accidents, aging, and industrial disasters. Accordingly, the importance of biocompatible materials for treating and recovering human tissues or functions is increasing. Furthermore, materials with various biological functions that interact with surrounding tissues and cells are being researched and developed, instead of materials that simply replace damaged tissues. This study analyzes the research and development trends of biocompatible materials and examines the latest status of technological developments. Biocompatible materials generally include metals, ceramics, polymers, gels, and composite materials. Polymer materials began to be widely used as biocompatible materials from the mid-20th century. Recently, polymer-extracellular matrix (ECM) composite technology using ECMs, which exist naturally in the human body, is drawing considerable attention. Thus, the ultimate objective of this study is to establish strategies to secure key patents in the field of polymer materials among various biocompatible materials. To this end, quantitative and qualitative analyses are conducted based on patents published in South Korea, the U.S., Japan, and Europe by country, keyword, applicant, and inventor. Based on the results of these analyses, this study examines recent patent application trends, and establishes directions for technology development and strategies for developing key technologies in this field. Consequently, four major strategies are established: technology development, purchasing patents, setting cross-licenses, and bypass technology development. Subsequently, concrete patent acquisition plans in line with each direction are conceived. In addition, four industries related to biocompatible materials (over-the-counter drugs, prescription drugs, medical materials, and cosmetics) are selected, the key patents in each industry are examined, and patent acquisition scenarios are suggested.

Synthesis of Highly Durable Sulfonated Polyketone Fibers by Direct Sulfonation Reaction and Their Adsorption Properties for Heavy Metals Abstract In this study, sulfonated polyketone (SPK) cation exchange fibers were prepared by direct sulfonation with various concentration of sulfonating agent and sulfonation time. Fourier-transform infrared (FTIR) spectrum analysis was performed to confirm the structure of the sulfonated polyketone cation exchange fibers. The degree of sulfonation (DOS) and water uptake (W.U) of SPK cation exchange fibers were measured by gravimetric method and ion exchange capacity (IEC) was measured by titration method, respectively. The DOS of the SPK cation exchange fibers increased with sulfonation time and concentration of sulfonating agent. The SPK cation exchange fibers sulfonated for 15 min at a mole ratio of 1:2 of polyketone to chlorosulfonic acid had the DOS of 47%, ion exchange capacity 3.36 meq/g, and water content 35.1%, showing the best performance.

Examination of Selection and Combination of Water-Absorbing Agent to Blend with Polyvinyl Alcohol (PVA) in Preparing CO 2 -Separation Membrane with High-Performance Abstract In the present study, the selection and combination of the water-absorbing agent to blend with polyvinyl alcohol (PVA) for the preparation of a high-performance CO2-separation membrane were examined by evaluating the separation performance of the resulting membrane. The separation performance of a two-layer membrane prepared by stacking and a single-layer membrane prepared by blending were also compared, where the latter was found to be superior. The selection of a water-absorbing agent with higher water absorption and compatibility with PVA is important in the preparation of a high-performance separation membrane by blending. The high-performance CO2-separation membrane was prepared by blending PVA with two types of water-absorbing agents. In addition, the variation in the composition ratio of two water-absorbing agents further improved the CO2-separation performance. Accordingly, the high-performance CO2-separation membrane was successfully prepared by combining PVA with two water-absorbing agents.

Preparation of High-Elongation and High-Toughness Poly( l -lactide) Using Multi-Arm Methyl- β -Cyclodextrin-Poly( l -lactide) Abstract We synthesized 3–16 armed methyl-β-cyclodextrin-poly(l-lactide) (MCD-PLLA) polymers, and then blended them with PLLA. The addition of MCD-PLLA with 9 or 12 arms to PLLA dramatically increased the elongation at break (E) and toughness (UT) of PLLA with little affecting its Tg and tensile strength. The highest E and UT were obtained to be 127% and 6.85 GJ/m3, respectively, for PLLA blends containing these MCD-PLLAs. It was confirmed that the MCD-PLLA served as a nucleation agent for PLLA, inducing PLLA chains to form smaller and more uniform-sized crystallites compared with pure PLLA. The homogeneous fragmentation of these small and uniform-sized crystallites during tensile deformation consequently resulted in such a remarkable increase in E and UT. In contrast, the addition of MCD-PLLAs with more than 12 arms to PLLA decreased its E and UT mainly due to preferential crystallization by themselves.

Eco-Friendly Nanocellulose Embedded Polymer Composite Foam for Flame Retardancy Improvement Abstract Delaying flame propagation in the event of a fire can increase the likelihood of preserving life and alleviating property damage. Here, a strategy for flame retardant polymer composite foam is proposed, which enables the improved performance, good formability, and reduced environmental burden while burning. The strategy is to incorporate sylilated nanocellulose into a polyurethane matrix containing a conventional flame retardant, Tris(2-chloroethyl) phosphate (TCEP). This strategy leads to the generation of char layer faster during combustion, resulting in a delayed flame propagation. The limiting oxygen index (LOI) of the samples increased by 28%, and the production rate of toxic gas emission was considerably reduced. The chemical, thermal, mechanical, and morphological analyses were carried out to understand the underlying physics.

Improvements of the Electrical Conductivity and EMI Shielding Efficiency for the Polycarbonate/ABS/Carbon Fiber Composites Prepared by Pultrusion Process Abstract The electrical conductivity, electromagnetic interference (EMI) shielding efficiency, and the morphological and mechanical properties of the polycarbonate/poly(acrylonitrile-butadiene-styrene) (ABS) (70/30)/carbon fiber (CF) composites were studied. The composites were prepared by two different methods, i.e., the pultrusion process and screw extrusion. The composite prepared by the pultrusion process showed higher electrical conductivity of 1.05×101 S/cm and EMI shielding efficiency of 37.6 dB compared to the composite prepared by screw extrusion of 5.20×10−1 S/cm and 6.8 dB at 10 GHz. The increase in the shielding efficiency of electromagnetic wave by 30.8 dB was due to the increased fiber length when the composite was prepared by the pultrusion process. The tensile and flexural strengths of the polycarbonate/ABS (70/30)/CF composite prepared by the pultrusion process were slightly higher by 8.2 and 7.0% compared to those of the composites prepared by screw extrusion, respectively. The above results suggest that the pultrusion process is a superior method to prepare the polycarbonate/ABS (70/30)/CF composites with favorable electrical and mechanical properties.

PPE/Nylon 66 Blends with High Mechanical Toughness and Flame Retardancy Abstract Poly(2,6-dimethyl-1,4-phenylene ether) (PPE)/Nylon 66 blends have been considered as the potential heat resistant engineering plastics with high mechanical toughness and flame retardancy, suitable for high temperature applications. However, incompatibility between PPE and Nylon 66 and poor thermal stability of Nylon 66 degrade mechanical toughness and flame retardancy. In this work, for the first time, the PPE/Nylon 66 blends with high mechanical toughness and flame retardancy simultaneously have been prepared through newly synthesized compatibilizer of PPE grafted with fumaric acid (PPE-g-FA) and environmental-friendly non-halogen organic phosphinate flame retardant. The PPE/Nylon 66 blend achieved not only V0 grade flame retardancy with the help of improved fire resistance through the solid phase reaction of non-halogenic flame retardant, but also large impact strength larger than 10 kJ/m2 due to the strong compatibility of PPE-g-FA.

Compatibilization of LDPE/PA6 by Using a LDPE Functionalized with a Maleinized Hyperbranched Polyester Polyol Abstract Low density polyethylene (LDPE)/polyamide6 (PA) blends can lead to a synergy between the properties of these materials. These blends are employed mainly in the packing industry, especially in food factories. The problem of this system is that it is inmiscible, hence requires to be compatibilized. The aim of this study is to compatibilize blends of LDPE/PA6 using a LDPE modified with a maleinized hyperbranched polyol polyester (LDPE-g-MHBP) as a compatibilizing agent. Therefore blends of LDPE (50 wt%)/PA (50 wt%) were prepared by using proportions of 5 (Blend5), 10 (Blend10), 15 (Blend15) and 20 (Blend20) wt% of the LDPE-g-MHBP of the total mix. On the other hand, to determine the efficiency of the LDPE-g-MHBP as a compatibilizing agent, a Blend0 (blends of LDPE (50 wt%)/PA (50 wt%) without LDPE-g-MHBP) was used as the control sample. By infrared (IR) analysis was evidenced the interactions between PA and LDPE-g-MHBP. By differential scanning calorimetry analysis (DSC) was observed that the LDPE-g-MHBP increased the crystallinity of the LDPE phase, but the behavior was opposite to PA. The thermal stability and the viscosity of the blends obtained with LDPE-g-MHBP were higher than those of the Blend0. Scanning electron microscopy (SEM) analysis revealed that the LDPE-g-MHBP ostensibly improved the miscibility of the LDPE/PA blends.

Preparation of Poly(phenylene sulfide)/Nylon 6 Grafted Graphene Oxide Nanocomposites with Enhanced Mechanical and Thermal Properties Abstract Poly(phenylene sulfide) (PPS) is an attractive polymer in engineering plastics because of its high mechanical strength and thermal stability. Herein, poly(phenylene sulfide)/nylon 6 grafted graphene oxide (PPS/NGO) nanocomposites were prepared by micro-compounding, where NGO is prepared via ring-opening polymerization of ε-caprolactam on the graphene oxide (GO), which has carboxylic acid groups that can act as an initiator. Since nylon 6 is known to be able to blend with commercial PPS, nylon 6 moiety in NGO can increase mechanical properties of PPS, especially by forming PPS/NGO nanocomposites with improved toughness. Moreover, graphene nanosheets can provide improved mechanical strength and thermal stability because of their mechanically reinforcing and thermal barrier effects. For example, if a PPS/NGO nanocomposite with 0.03 wt% of NGO was prepared, the tensile strength and elongation at break values increased by 32% and 30%, respectively, compared to neat PPS. Also, the thermal decomposition temperature for 5% weight loss increased from 481 to 488 °C, indicating the improved thermal stability. These improved properties can be attributed to the well-dispersed NGO in the PPS matrix, as confirmed by the morphological studies using SEM and EDS mapping.

Improvement of Biodegradability and Biocompatibility of Electrospun Scaffolds of Poly(butylene terephthalate) by Incorporation of Sebacate Units Abstract Incorporation of aliphatic units to poly(butylene terephthalate) (PBT) gives rise to biodegradable copolymers with tunable properties (e.g., degradability), depending on the selected comonomer and the specific composition. Specifically, a low molecular weight poly(butylene sebacate-co-terephthalate) (PBSeT) with a high ratio of aliphatic sebacate units (i.e., 70 mol-% with respect to the total dicarboxylate content) has been employed in this work to get new electrospun biodegradable scaffolds. Appropriate electrospinning conditions have been found despite the limited copolymer molecular weight. In addition, PBSeT has been employed to improve biocompatibility and biodegradability of scaffolds based on the PBT homopolymer. Scaffolds with different properties have been prepared following two strategies: Electrospinning of single solutions of PBT and PBSeT mixtures and co-electrospinning of independent PBT and PBSeT solutions. Characterization involved spectroscopic (FTIR, NMR), calorimetric (DSC, TGA) and surface hydrophobicity analyses. Hydrolytic and enzymatic degradation studies demonstrated the success of the approach due to the susceptibility of the PBSeT component towards the enzymatic attack with lipases from Pseudomonas cepacia and even towards high temperature hydrolysis.