Polyethylene terephthalate etching

Membranes with very regular pores of sizes down to around 10 nm can be prepared by track-etching [10], and, in principle, those membranes can be used for the fractionation of macromolecules in solution. A relatively thin (<35 pm) polymer film (typically from polyethylene terephthalate)/PET/or aromatic polycarbonate/PC/) is first bombarded with fission particles from a high-energy source. These particles... 

Other recent applications of AFM-SECM included the study of the iontophoretic transport of [Fe(CN)6]4 across a synthetic track-etched polyethylene terephthalate membrane by Gardner et al. [193]. They made the structure and flux measurements at the single pore level and found that only a fraction of candidate pore sites are active in transport. Demaille et al. used AFM-SECM technique in aqueous solutions to determine both the static and dynamical properties of nanometer-thick monolayers of poly(ethylene glycol) (PEG) chains end-grafted to a gold substrate surface [180]. 

Polyethylene terephthalate cannot be solvent-cemented or heat-welded. Adhesives are the prime way of joining PET to itself and to other substrates. Only solvent cleaning of PET surfaces is recommended as a surface treatment. The linear film of polyethylene terephthalate (Mylar) provides a surface that can be pretreated by alkaline etching or plasma for maximum adhesion, but often a special treatment such as this is not necessary. An adhesive for linear polyester has been developed from a partially amidized acid from a secondary amine, reacted at less than stoichiometric with a DGEB A epoxy resin, and cured with a dihydrazide.72... 

The brittle cracking and subsequent debonding of films deposited on flexible substrates subjected to uniaxial strain is described theoretically and illustrated with Ni films evaporated on ion-etched polyethylene terephthalate (PET). It is shown that, if the materials deform elastically, the shear strength of the interface, x, may be evaluated from the length,... 

Ion-track etching is a unique technique for the production of polymer membranes with statistically distributed nanopores. The size, shape, and density of these pores can be varied in a controllable manner by achieving the required transport and retention membrane characteristics (Apel 2001). The widely used polymer materials for ion-track membranes production are polyethylene terephthalate (PET) and polycarbonate (PC) thin films. The commercially available polymer membranes contain... 

Recently, a new approach using enzymes to modify material (or nanomaterial) surfaces has been developed. This approach utilizes enzymatic hydrolysis or degradation to mildly etch the material surfaces and thus CTeate desirable surface structures or properties [45]. Many polymers, including polyvinyl chloride (PVC), polyaayloni-trile, polyethylene terephthalate, and polyamides, have been modified by this method. In a recent study, PVC tubes were soaked in Rhizopus arrhizus lipase to create nanometer surface features that exhibited antibacterial properties [60]. Enzymatic modification demonstrates great potential and promise for biomedical and nanomedicine applications due to its biocompatible, environmentally friendly, and simple process. 

Surface treatments recommended specifically for PBT include abrasion and solvent cleaning with toluene. A medium-strength bond can be obtained with polyethylene terephthalate plastics and films by abrasion and solvent cleaning. Gas plasma surface treatments and chemical etch have been used where maximum strength is necessary. Solvent cleaning of PET surfaces is recommended. 

To prepare membranes with artificial nanochannels, one can start with several polymer materials such as polyimide (PI), polycarbonate (PC), and polyethylene terephthalate (PET). A prerequisite to apply these kinds of polymers for nanochannel fabrication is that they are easy to process and susceptible to different etching techniques to produce nano-sized channels of different morphologies. Current methods for this purpose include ion-track-etching, electrochemical etching, and laser techniques. Once the nanochannels have been produced, one needs to functionalize the channel inner wall to obtain different functions. Following are some examples of polymer decorated nanochannels. 

The list of polymers known to respond satisfactorily to permanganic etching is now long and continually growing. It consists of linear and branched polyethylene, four isotactic polyolefins (polypropylene, polystyrene, poly(4-methylpentene-l) and poly(butene-l)), related atactic polymers, poly(vinylidene fluoride) (hereafter denoted PVF2), PEEK, and poly(ethylene terephthalate) (PET), together with various copolymers and others such as ethylene propylene rubbers and ethylene-propylene-diene (EPDM) terpolymer. 

SEM photomicrograph of the smoothed and toluene-etched surfece of a PET ultra-low-density polyethylene (ULDPE)-g-DEM blend obtained in a discontinuous mixer by adding Ti(OBu)4 as a transesterification catalyst. (From M. B. ColtelH, Catalysed Reactive Compatibilization of Polyolefin and Poly(ethylene terephthalate) Blends Reactions Mechanisms and Phase Morphology Development, Ph.D. thesis. University of Pisa, Italy, 2005.)... 

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