Backbone Of Poly Research Articles

Synthesis of full bio‐based, fast degradable, and high strength copolyesters: Poly(butylene succinate‐sebacicate‐salicylicate‐malicate)

AbstractThe presence of petroleum‐based monomers in the backbone of poly(butylene succinate‐co‐adipate) (PBSA) restricts its application in light of increasingly stringent environmental regulations. In this study, a novel full bio‐based biodegradable random copolymer poly(butylene succinate‐sebacicate‐salicylicate‐malicate) (PBSSeSa‐c‐M) was designed and synthesized. The comprehensive study encompassed the structural alterations, properties, and degradation resulting from the inclusion of salicylicate sebacicate and malicate units. The incorporation of salicylic acid effectively enhanced the tensile modulus of the copolymer, due to the effect of rigid benzene ring. Meanwhile, the addition of sebacic acid regulated the degradation rate. The introduction of malic acid significantly improved the rheological properties, endowing the copolymer with exceptional processability. The obtained high molecular weight PBSSeSa‐c‐M exhibited outstanding film‐blowing processability with an intrinsic viscosity of 1.58 dL/g and melt flow rate of 7.34 g/10 min. The tensile modulus reaches 235.43 MPa that is comparable to commercial PBSA. Besides, the degradation of PBSSeSa‐c‐M reaches 18.92% over 4 weeks, far higher than that of PBSA. In conclusion, this work provides a design and synthesis for a new kind of biodegradable copolyester that satisfies the requirement of rapid degradation in single‐use plastics.

Synthesis, Properties, and Degradation of Poly(butylene succinate-co-sebacicate-co-salicylicate) Copolyesters

Since monomers in backbone of poly(butylene succinate-co-adipate) (PBSA) are not entirely derived from bio-based sources, limiting its application in the face of increasingly stringent environmental policies. In this study, a novel full bio-based biodegradable random copolyester poly(butylene succinate-co-sebacicate-co-salicylicate) was successfully synthesized. Detailed investigations were conducted on the structural, mechanical, and degradation characteristics resulting from the introduction of salicylicate and sebacicate units. Introduction of salicylicate units effectively enhanced the mechanical performance. In comparison to PBSA, the tensile modulus of copolymer increased by 20.2% with 10% salicylic acid. Introduction of sebacicate units significantly altered the crystalline structure of copolymer and promote the degradation efficiency. Considering both mechanical strength and degradation efficiency, the copolyester with 2% salicylic acid and 20% sebacic acid was found to meet practical application requirements. Relative to PBSA, this copolymer demonstrated a 13.7% increase in tensile modulus and a remarkable 143.1% improvement in degradation efficiency. Importantly, this study focused on the effect of the bio-based rigid monomer salicylic acid and the soft monomer sebacic acid on the degradability of biodegradable polymers. The insights gained provide valuable guidance for tailoring the synthesis of degradable plastics to meet diverse degradation cycle requirements.

Solution-processable thermally activated delayed fluorescence red emitters poly(carbazole-fluorene) containing naphthalene imide units

In recent years, the development of solution-processable red-emitting TADF materials has progressed slowly compared to green and blue TADF materials in terms of device efficiency and color purity. This study reports a series of solution-processable red-emitting TADF polymers PCzF-mCP-PXZNAI-X (X = 5, 15, 25, 35), which are designed and synthesized by connecting TADF units (6-(10H-phenoxazin-10-yl)-2-phenyl-1H-benzo[de]isoquinoline-1,3(2H)-dione, PXZNAI) and host units (1,3-bis(N-carbazolyl)benzene, mCP) to the pre-obtained backbone poly(carbazole-fluorene) (PCzF-N3) through the “click” reaction. All the target TADF polymers exhibited good solubility and high thermal stability. Spin-coating PCzF-mCP-PXZNAI-35 as the emission layer, the solution-processed undoped device showed stable red emission with the maximum emission wavelength (λEL) of 647 nm in the operating voltages 8 V–17 V, the maximum external quantum efficiency (EQEmax) of 0.32% and the maximum luminance (Lmax) of 127 cd/m2. The doped device based on PCzF-mCP-PXZNAI-35 using CBP as host material showed orange-red emission with λEL of 619 nm, EQEmax of 2.34% and Lmax of 1938 cd/m2. This result provides a new strategy for the construction of solution-processable stable red-emitting TADF materials.

A Transparent, Healable and Recyclable Alicyclic Poly(ether-b-amide) Multiblock Copolymer with Ultrahigh Toughness.

Self-healing polyamide multiblock copolymer with robust mechanical properties is highly desired. Here, an alicyclic diamine monomer, isophoronediamine (IPDA), with asymmetric structure and substantial steric hindrance was incorporated into the backbone of poly(ether-b-amide) multiblock copolymer. Based on the phase-lock effect, the mechanical properties and segmental mobility of copolymers can be modulated on a large scale via adjusting the molecular weight of hard segments. An extraordinary tensile strength of 32.0 MPa and an excellent elongation at break of 1881 % were simultaneously achieved, which leaded to a record-high toughness of 328.9 MJ m-3 for self-healable polyamide elastomers. The synergism between the dynamic H-bonding networks and the diffusion of polymer chains contributed to a balance between the mechanical performance and self-healing efficiency of copolymers. Due to the adjustable mechanical performance, rapid scratch self-healing ability and superior impact resistance, the resultant copolymers showed great potential in the fields of protective coatings and soft electronics.

Probing Interfacial Behavior and Antifouling Activity of Adsorbed Copolymers at Solid/Liquid Interfaces.

Polymers containing poly(ethylene glycol) (PEG) units can exhibit excellent antifouling properties, which have been proposed/used for coating of biomedical implants, separation membranes, and structures in marine environments, as well as active ingredients in detergent formulations to avoid soil redepositioning in textile laundry. This study aimed to elucidate the molecular behavior of a copolymer poly(MMA-co-MPEGMA) containing antiadhesive PEG side chains and a backbone of poly(methyl methacrylate), at a buried polymer/solution interface. Polyethylene terephthalate (PET) was used as a substrate to model polyester textile surfaces. Sum frequency generation (SFG) vibrational spectroscopy was applied to examine the interfacial behavior of the copolymer at PET/solution interfaces in situ and in real time. Complementarily, copolymer adsorption on PET and subsequent antiadhesion against protein foulants were probed by quartz-crystal microbalance experiments with dissipation monitoring (QCM-D). Both applied techniques show that poly(MMA-co-MPEGMA) adsorbs significantly to the PET/solution interface at bulk polymer solution concentrations as low as 2 ppm, while saturation of the surface was reached at 20 ppm. The hydrophobic MMA segments provide an anchor for the copolymer to bind onto PET in an ordered way, while the pendant PEG segments are more disordered but contain ordered interfacial water. In the presence of considerable amounts of dissolved surfactants, poly(MMA-co-MPEGMA) could still effectively adsorb on the PET surface and remained stable at the surface upon washing with hot and cold water or surfactant solution. In addition, it was found that adsorbed poly(MMA-co-MPEGMA) provided the PET surface with antiadhesive properties and could prevent protein deposition, highlighting the superior surface affinity and antifouling performance of the copolymer. The results obtained in this work demonstrate that amphiphilic copolymers containing PMMA anchors and PEG side chains can be used in detergent formulations to modify polyester surfaces during laundry and reduce deposition of proteins (and likely also other soils) on the textile.

Remarkably enhanced crystallization behavior and impact toughness of poly(ethylene terephthalate) via introducing phenyl–terminated hyperbranched polyester

Rigid benzene ring structure on the backbone of poly(ethylene terephthalate) (PET) results in its slow crystallization rate. In present work, we proposed to incorporate a versatile nucleating agent with the combination of efficient heterogeneous nucleation and promoting crystal growth. Herein, phenyl–terminated hyperbranched polyester (HBP-Bz) was introduced. Polarized optical microscopy and differential scanning calorimetry results showed that HBP-Bz demonstrates superior heterogeneous nucleation effect. The crystallization temperature of PET is increased by nearly 20 K with the addition of 1% HBP-Bz. The main reason for HBP-Bz to accelerate PET crystallization is to increase the nucleation rate and density, and further increase in HBP-Bz content is favorable for the elevation of crystal growth rate of PET. A possible crystallization promotion mechanism of HBP-Bz on PET was proposed on the basis of dynamic viscoelasticity analysis. Moreover, effectively improved crystallinity and refined spherulites lead to remarkable elevation in mechanical properties especially the toughness.

Cu(I) catalyzed ATRP for the preparation of high-performance poly (vinylidene fluoride)-g-poly 2-(dimethylamino)ethyl methacrylate crosslinked anion exchange membranes for enhanced acid recovery

The exclusive selectivity feature of an anion exchange membrane (AEM) makes it a core component of the diffusion dialysis (DD) process. Herein, we have developed a novel synthetic route for the preparation of AEMs with a controlled graft length and density by grafting 2-(dimethylamino)ethyl methacrylate (DMA) chains from the backbone of poly(vinylidene fluoride) (PVDF) by Cu(I) catalyzed atom transfer radical polymerization to produce PVDF-g-PDMA copolymer, which is converted to AEM by the reaction with α,α’-dichloro-p-xylene (XDC). XDC induces positive charge on the membrane surface and increases the hydrophilicity of the membrane. It also acts as a crosslinker and helps to create a network structure in the membrane, which increases overall membrane stability. The AEMs are used to separate hydrochloric acid from its mixture with metal salts by diffusion dialysis. A representative AEM containing 12% w/w PDMA, abbreviated as ATM-2, show diffusion coefficient (UH+) and separation factors (S) of 0.049 m/h and 117, respectively during the separation of HCl from 2 M HCl + 0.09 M FeCl2 solution. ATM-2 also shows higher UH+ and S values for the separation of HCl with its mixture of different metal salts, i.e., NaCl, CuCl2, and AlCl3. ATM-2 membrane endures a small loss of 1.5% and 3.2% in UH+ and S values, respectively, after submerging in a 2 M acid/salt mixture solution for 60 days. This confirms the good acid stability of the AEM. The results indicate the reasonable potency of the prepared AEMs to be a suitable candidate for DD applications.

Synthesis and thermoresponsive behavior of double hydrophilic graft copolymer based on poly(2-methyl-2-oxazoline) and poly(2-ethyl-2-oxazoline)

A recent challenge in polymer self-assembly is the utilization of double hydrophilic graft copolymers (DHGC) in view of biomedical applications. Here we describe, for the first time, a platform of biocompatible DHGC fully based on poly(2-alkyl-2-oxazoline) leading to stimuli-responsive self-assemblies. This original DHGC platform was composed of backbone poly(2-methyl-2-oxazoline-co-2-pentyl-2-oxazoline) (P(MeOx-co-PentOx)) and poly(2-ethyl-2-oxazoline) (PEtOx) grafts. A “grafting onto” approach based on the combination of cationic ring-opening polymerization (CROP) technique and “click chemistry” CuAAc reaction, was successfully used to synthesize poly(2-methyl-2-oxazoline-co-2-pentyl-2-oxazoline)-g-poly(2-ethyl-2-oxazoline) (P(MeOx-co-PentOx)-g-PEtOx) copolymer conjugates of varying backbone and side chain lengths. These purely hydrophilic copolymers demonstrated self-assembling behavior in aqueous solution, showing a characteristic double hydrophilic behavior originating from building blocks immiscibilities. Self-associated structures with spherical morphologies have been evidenced by DLS and cryo-TEM. The sizes and the efficiency of self-association were mainly controlled by the concentration of the graft copolymer and by the molar ratio of the different hydrophilic compounds. In addition, thermoresponsive properties of these copolymers were studied by turbidimetry and DLS. From purely hydrophilic at low temperature, the copolymers showed amphiphilic characters at temperatures close to the cloud points (CP). Interestingly, cloud points were not controlled by the PEtOx graft length as it has been reported for PEtOx homopolymers but it depended mainly upon the PEtOx content of the copolymer, with a critical value around 75 PEtOx wt%. Addition of a kosmotropic salt (Na2SO4) allowed to trigger CPs from 80 °C till 26 °C. The self-assembling properties of this family of hydrophilic and biocompatible copolymers may offer promising prospect in the field of biomedical applications as bioreactors.

Preparation of Thermo- and pH-Responsive Microgels Based on Complementary Nucleobase Molecular Recognition.

Complementary interactions between the natural nucleobases is one of the important ways of biomolecular recognition. Although scientists have introduced such supramolecular noncovalent interactions into biomimetic materials through different approaches in recent years, further research is still needed to confer structural features of biomolecules into emerging stimuli-responsive microgels. In this study, a series of bis-thymine end decorated flexible poly (N-isopropyl acrylamide) (T-PNIPAM-T) are obtained through a thymine esterified RAFT agent. Meanwhile, a rigid polymeric backbone poly[1-(4-vinyl benzyl)] adenine (PS A), including several pendant adenines on the side chain is prepared. Through nucleobase complementary pairing subtle supramolecular cross-linked 3D networks are constructed, and further self-assembled to form microgels under the balance between hydrophilicity and block flexibility. More importantly, such supramolecular 3D microgels show volumetric shrinkage in different water content environments and the assembly behavior under thermo and pH stimulated conditions. This exploration is expected to play an important value and significance in the field of biomimetic controlled release of soft matter in the future.

Continuously Multiplexed Ultrastrong Raman Probes by Precise Isotopic Polymer Backbone Doping for Multidimensional Information Storage and Encryption.

Raman-based super multiplexing has attracted great interest in imaging, biological analysis, identity security, and information storage. It still remains a great challenge to synthesize a large number of different Raman-active molecules to fulfill the Raman color palette. Here, we report a facile and systematic strategy to construct continuously multiplexed ultrastrong Raman probes. By precisely incorporating different ratios of 13C isotope into the backbone of poly(deca-4,6-diynedioic acid) (PDDA), we can obtain a library of PDDAs with tunable double-bond Raman frequencies and adjustable intensity ratios of two triple-bond (13C≡13C and 12C≡12C) Raman peaks, while retaining the ultrastrong Raman signals and physicochemical properties of the polymer. We also demonstrate the successful application of 13C-doped PDDAs as security inks to generate a novel 3D matrix barcode system for information encryption and high-density data storage. The isotopically doped PDDA series herein pave a new way to advance Raman-based super multiplexing for diverse applications.

Design, synthesis and characterization of anion exchange membranes containing guanidinium salts with ultrahigh dimensional stability

Anion exchange membranes (AEMs) with high anionic conductivity and mechanical robustness are required for alkaline membrane fuel cells (AMFCs) and are significantly influenced by the water uptake (WU) of the membrane. When the swelling ratio (SR) becomes too large, the mechanical integrity of the membrane becomes compromised, which may have catastrophic consequences for the fuel cell. Herein, backbone Poly(arylpiperidinium) (PAP) with no ether bond, rigidity and hydrophobic structure was combined with the hydrophobic guanidinium salt to design and synthesize a series of AEMs containing novel guanidinium salts through a simple and efficient route. The introduction of the guanidinium salt structure with large steric hindrance significantly improved the dimensional stability of the AEMs; the WU of membrane material at 80 °C was under 12%, and the SR was less than 3%. In addition, the AEMs showed excellent thermal stability, with the decomposition temperatures of the guanidinium group and the backbone being 350 °C and 450 °C, respectively.

Absorption and fluorescence spectra of conjugated polymers poly(propylene oxide)–poly(phenylene ethynylene) interpreted by Franck–Condon simulation

AbstractAbsorption and fluorescence spectra of the poly(propyleneoxide)–poly(phenylene ethynylene) with long polymer chains in the experiment are investigated by the Franck–Condon simulation with small polymer chains in the theory. Electronic calculations with time‐dependent density functional (TDDFT) indicate that vibronic spectra come from S1(ππ*) excitation and de‐excitation. Good agreement between Franck–Condon simulated and experimentally measured absorption and fluorescence spectra in three kinds of solutions is achieved. However, vibronic spectral analysis reveals that vibronic motion mechanisms are quite different for simulated absorption and fluorescence spectra. For absorption spectra, vibronic spectra are dominated by one most active mode localized in triple bond carbon–carbon stretch motion on backbone of the poly (phenylene ethynylene), and simulated absorption spectra indicate that the long chains can be as stable as short chains on the electronic ground state in comparison with experimental spectra in all solvents. In the case of fluorescence spectra, this most active mode is spitting into several equally active modes with very close values in vibrational frequencies, and thus, the spitting modes and mode couplings among those spitting dominate vibronic spectra. Simulated fluorescence spectra indicate that the only short chains are stable on the electronic excited state in comparison with experimental spectra in all solvents. Nevertheless, the present simulation concludes that both absorption and fluorescence spectra are induced mostly by the active normal mode in triple bond carbon–carbon stretch motion on backbone of poly(phenylene ethynylene). The present work provides physical insight for analyzing observed vibronic spectra of similar conjugated polymers and for designing novel optoelectronic materials.

Controllable Poly(L-lactic acid) Soft Film with Respirability and Its Effect on Strawberry Preservation

Gas permeability of films is essentially important for fresh products packaging. The flexible poly(e-caprolactone) (PCL) was incorporated into the backbone of poly(L-lactic acid) (PLLA) to improve the flexibility and gas permeability of PLLA. The effects of different PCL middle blocks on the mechanical properties, oxygen (O2), carbon dioxide (CO2) and water vapor permeative properties of PLLA-PCL-PLLA triblock copolymers were evaluated, as well as its preservation effect on strawberry. The results showed that both the PCL and PLLA blocks kept amorphous state, and phase separation occurred in this immiscible system. The PCL play a role of gas passage, the CO2 permeability and CO2/O2 perm-selective ratio of neat PLLA film improved 2–3 times with the incorporation of higher molecular weight PCL. In addition, the PLLA-PCL-PLLA films presented a better toughness after large insertion of flexible PCL. Storing experiments showed that the low O2 and high CO2 atmosphere was established inside the package due to the good gas exchange performance of films. Moreover, strawberries still maintained the good sensory quality and Vitamin C contents on 24th day. Such biodegradable PLLA soft films are of great potential in fresh product packaging.

(Invited) Design of Solid Polymer Electrolytes with Poly(Ethylene Oxide) Backbone for Lithium Batteries Operated at Room Temperature

Replacing organic liquid electrolytes with all-solid polymer electrolytes (SPEs) remedies various safety problems related to lithium ion batteries (LIBs). This work focuses on the design of SPE membranes with a backbone of poly(ethylene oxide) (PEO), containing no solvent, ionic liquid, oligomer, or semisolid additives, for LIBs operated at room temperature. Despite their ability in dissociating the lithium salt and Li+-ion coordination, PEO-based SPEs exhibit poor ionic conductivity at room temperature because their polymer chains tend to crystallize. Instead of adding inert fillers to suppress the crystallization tendency, this work employs functional linkers, such as silsesquioxanes, isocyanates, and triglycerides, to crosslink the PEO-based chains and produce a three-dimensional polymer network. These crosslinkers serve as hubs to facilitate effective Li+-ion motion. A low glass transition temperature and a low activation energy for ion conduction confirm the high segmental mobility of the polymer chains. When incorporated with a porous PVDF membrane, the SPEs exhibit high mechanical, chemical, and electrochemical stability, showing an ionic conductivity of ~ 10−4 S cm−1 and a stable potential of >5 V (vs. Li/Li+) at room temperature. The resulting Li|SPE|LiFePO4 batteries deliver discharge capacities of >155 and >135 mAh g−1 (based on LiFePO4) at 0.1 and 1 C-rates, respectively, at room temperature with an excellent charge-discharge cycling stability (>300 cycles).

An anti-stress relaxation, anti-fatigue, mildew proof and self-healing poly(thiourethane-urethane) for durably stretchable electronics

Considering the complicated environment in daily use of stretchable devices, the capabilities of anti-stress relaxation, anti-fatigue, anti-fungal and self-healing are very much appreciated, and the above four functionalities largely depend on the elastic matrix. Here, these demands are fulfilled by a poly(thiourethane-urethane) elastomer CBPU-3. In detail, a large amount of cyclohexane rings, with completely reversible boat–chair conformational transition, are introduced into the backbone of poly(thiourethane-urethane), and such non-planar ring imparts molecular elasticity and modulus into the elastomer, resulting in remarkable anti-stress relaxation and anti-fatigue abilities. Even after 20 h fixation at 300% strain and 1000 times cyclic tensile (50% strain), the recovery ratio could still be higher than 98%, and its stable microstructure is proved by SAXS scattering patterns. In addition, the thioether bond ensures the effective mildew proof ability, and the mechanical properties and transmittance change little even after a severe mildew pollution for 30 days. Simultaneously, the relatively lower bond energy of C-S (62.0 Kcal/mol) in thiourethane bonds endowes the poly(thiourethane-urethane) with self-healing capability (highest: 40 μm/min at 80 °C). Finally, the durability and usability of the deformable resistive sensor array based on this elastomer as the matrix are drastically enhanced due to the above integrated functionalities.

Simultaneously Enhancing Photoluminescence Quantum Efficiency and Optical Gain of Polyfluorene via Backbone Intercalation of 2,5‐Dimethyl‐1,4‐Phenylene

AbstractSimultaneous enhancement of photoluminescence quantum efficiency (PLQE) and optical gain in semiconducting polymer films is desirable for optically‐ or electrically‐pumped organic solid‐state lasers. In this work, a simple self‐dilution effect is achieved by introducing a small amount (≈10% by weight) of 2,5‐dimethyl‐1,4‐phenylene (DP) units in the backbone of poly(9,9‐dioctylfluorene) (PFO). The resulting copolymers, compared with PFO (PLQE 39%), exhibit a significantly increased PLQE (66%) while keeping similar absorption and photoluminescence profile, concomitant with an enhancement in optical gain properties. The radiative decay rate increases sharply along with a sustaining reduction in the non‐radiative decay rate in these copolymers, following similar principle of physical dilution of a luminescent compound in solution or in a polymer matrix. Among all the copolymers, the one containing 10% DP units exhibits the lowest amplified spontaneous emission/distributed feedback laser threshold (10.9 nJ/1.4 nJ, eightfold reduction), and the highest gain coefficient (54.4 cm−1). The results demonstrate that a moderate DP/fluorene ratio can maximize the beneficial self‐dilution effects. These investigations shed light on new design strategies to achieve conjugated polymers with concurrent high PLQE and large optical gain properties.

Synthetic Emission Tuning of Carborane-Containing Poly(dihexylfluorene)s

Incorporation of o-carborane into the backbone of poly(dihexylfluorene)s drastically affects emission properties due to an intramolecular charge-transfer state (ICT) that forms between the fluorene...

Evolution of Structure in a Comb Copolymer–Surfactant Coacervate

The interaction between a double-hydrophilic comb copolymer with the polyanionic backbone poly[methacrylic acid-stat-poly(ethylene glycol) methyl ether methacrylate] (PMAA–PEGMA) and the cationic s...

Excellent Toughening of 2,6-Diaminopyridine Derived Poly (Urethane Urea) via Dynamic Cross-Linkages and Interfering with Hydrogen Bonding of Urea Groups from Partially Coordinated Ligands

Conventional approaches to synthesize thermoplastic polyurethane (TPU) with excellent robustness are limited by a competing relationship between soft and hard segments for tuning mechanical properties in terms of chain flexibility and micro-phase separation. Herein, we present a facile and effective way of simultaneously improving the tensile strength, elongation, and toughness by constructing dynamic cross-linkages from metal-ligand interaction between Zn2+ and pyridine moiety in backbone of poly(urethane urea) (PUU) derived from 2,6-diaminopyridine and poly(propylene glycol). It was found that a Zn2+/pyridine ratio of 1:4 is the most effective for improving robustness. Specifically, tensile strength, elongation, and toughness could be remarkably increased to 16.0 MPa, 1286%, and 89.3 MJ/m3 with 226%, 29%, and 185% increments compared to uncomplexed PUU, respectively. Results from UV-vis, Fourier transform infrared spectroscopy (FTIR), cyclic tensile tests, and stress relaxation reveal that metal-ligand interaction significantly interferes with the hydrogen bonding of urea groups, thus leading to weakening of stiffness. Furthermore, half of vacant ligands enable dynamic complexation during stretching, which consequently ensures constant noncovalent cross-linkages for constraining mutual chain sliding, contributing to simultaneous improvement of tensile strength, elongation, and toughness. This work provides a promising approach for designing TPU with excellent robustness.

Hemocompatibility study of surface-attached antibiofouling polymer monolayers

The interface between biomaterials and body fluid such as blood is a critical concern, because biomaterial-centered protein fouling and infection adversely affects the quality of life of many patients and cause major health care costs. Our research focused on polymer functionalization on surfaces to create antibiofouling interfaces (i.e. interfaces that repel the adhesion of proteins and microorganisms) in biomaterial-related applications, such as surgical instruments and blood-contacting biomedical devices. To this end, we have studied two hydrophilic polymers, namely poly(2-oxazoline) and poly(ethylene glycol), attached on metal oxide surfaces in brush configuration through a polyelectrolyte surface anchor, poly(L-lysine). Apart from antibiofouling properties, blood-contacting surfaces must also serve hemocompatibility. Here the hemocompatibility of antibiofouling monolayer on silicon oxide surfaces prepared from either poly(2-oxazoline) or poly(ethylene glycol) grafted on a main backbone poly(L-lysine), has been studied. The activation of C5a (complement system), TAT and kallikrein (coagulation cascade), PF4 and sP-selectin, (platelet activation) after incubation of the polymer-modified surfaces in whole blood was measured by means of ELISA kit. The results showed that in general, the contact between blood and polymer monolayer activated the complement system, but relatively did not activate the coagulation cascade and the platelet surface marker.