Upilex

UOP s Parex Process UOP Sulfolane process UOP Udex Process Upilex UpilexR... 

Kapton resin (5) (113) and Upilex (6) resin (114) are sold as films, partially polymerized resin coating solutions, and sinterable powders. Allied Signal also offers Apical polyimide film. 

An interesting aspect of dielectric constant thermometry is the small influence of a magnetic field. On the other hand, measurements depend on both the measuring frequency and voltage (see Figs 9.12 and 9.13). Figure 9.13 shows an example of the dependence on frequency of both the dielectric constant and loss for Upilex S [93]. 

Fig. 9.13. Dielectric properties of Upilex-S as a function of temperature at four measurement frequencies [93].

Upilex-S is a registered trademark of Ube Industries, Ltd., Tokyo, Japan. 

Figure 5.21 a shows an SEM micrograph (in cross section) of a feature ablated in doped PTFE, specifically 0.5% polyimide, at 12 J/cm2. The ablated feature is well defined and exhibits a smooth wall profile, typical of all blends having more than 0.1% (wt/wt) polyimide. The sidewall profiles of the less heavily doped blends are extremely vertical, having less taper than typically observed for more heavily doped PTFE films, e.g., 1.0 and 5.0% (Figures 5.21b and 5.21c, respectively) or Upilex-S polyimide, (Figure 5.21d). Ablation rates for a variety of PI-PTFE blends [0.2-5% polyimide (wt/wt) and neat polyimide] at 248 nm and 308 nm are shown in Figures 5.22 and 5.23, respectively.78...

Actymid, Aurum, Compimide, Cuming C-Stock, Duratron, Imidex, Kapton, Kerimid, Kinel, Meldin, Neopreg, Nolimid, Nomex, Sintimid, Upilex, Upimol, Vespel, Willmid. 

Commonly accepted practice restricts the term to plastics that serve engineering purposes and can be processed and reprocessed by injection and extrusion methods. This excludes the so-called specialty plastics, eg, fluorocarbon polymers and infusible film products such as Kapton and Upilex polyimide film, and thermosets including phenolics, epoxies, urea—formaldehydes, and silicones, some of which have been termed engineering plastics by other authors (4) (see Elastomers, synthetic-fluorocarbon elastomers Fluorine compounds, organic-tetrafluoroethylene copolymers with ethylene Phenolic resins Epoxy resins Amino resins and plastics). 

Recently Yamaoka and Miyata carried out the reactor irradiation at 20 K on two kinds of aromatic polyimides, Upilex-S and Upilex-R [51]. The stress-strain curves of irradiated Upilex-S films are depicted in Fig. 7. No essential changes in both elastic modulus and yield strength were observed for Upilex-S after irradiation up to 8 x 106 Gy, although a slight decrease of the ultimate elongation was detected. A similar tendency was found in the reactor irradiation of Upilex-R at 20 K, in spite of the fact that its structural unit of the main chain is different from that of Upilex-S. These results indicate that a homologue of aromatic polyimides exhibits the excellent radiation stability even at cryogenic temperatures as well as at ambient temperature. 

Materials. Kapton H (PMDA-ODA) films (25 um), PMDA-ODA polyamic acid and BPDA-PDA polyamic acid were obtained from Du Pont. Upilex S (BPDA-PDA) films were purchased from Ube Chemicals. KOH, NaOH, HC1, l-methyl-2-pyrrolidinone (NMP) and isopropanol were obtained from Aldrich. 

Methods. Polyamic acid in NMP was spin-coated onto a Si or Quartz wafer (diameter = 2.25 inches) coated with Cr, and then cured to polyimide at 400 °C. The purpose of the 500-750-A-thick layer of chromium is to enhance wettability and to give good reflectance to the Quartz wafer. Kapton H (PMDA-ODA) and Upilex S (BPDA-PDA) films were employed for gravimetric analysis. Around 5-um thick layers were used to measure the thickness change. The 100-1000-A-thick layers were employed to obtain XPS and ER IR spectra. The samples for contact angle measurement, XPS and ER IR were dried under vacuum at ambient temperature for 12-24 h and the samples for gravimetric analysis were dried at 85 °C for 12 h. The samples for film thickness measurement were fully re-cured to polyimide. 

Starting materials and solvents were purchased from Aldrich Chemical Co. acetonitrile (ACN), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP) were obtained anhydrous in Sure/Seal bottles and used as received. The polyamic acid of PMDA-ODA (2545 Pyralin) was supplied by DuPont. The soluble polyimide XU-218, derived from 3,3, 4,4 -benzophenone tetracarboxylic dianhydride (BTDA) and diamino-1,1,3-trimethyl-3-phenylindan isomers (DAPI) was purchased from Ciba-Geigy Corp. The acetylene terminated imide oligomer powder (Thermid MC-600) derived from BTDA, aminophenylacetylene, and 1,3-bis (2-aminophenoxy) benzene (APB) was obtained from National Starch and Chemical Company. Kapton Type II (PMDA-ODA) films were obtained from DuPont Co., Apical polyimide films were obtained from Allied Corp., and Upilex Type-S and Type-R polyimide films derived from 3,3, 4,4 -biphenyl tetracarboxylic dianhydride (BPDA) plus p-phenylenediamine (PDA) and ODA, respectively were obtained from ICI Americas Inc. 

Reduction of Upilex-R polyimide films in a solution containing 0.05 M anthracene (15 percent radical-anion) / 0.1 M TBAFB / NMP results in a broad visible absorbance (blue colored films) with a maximum at about 625 nm as shown in Figure 3. Since the potential of the anthracene couple is quite negative, BPDA-polymers can accept two electrons per imide unit which may contribute to the broad absorbance response for the reduced films. 

Figure 3. UV-Vis spectra for a 1 mil thick Upilex-R film after a 10 sec immersion in a O...

Generally, synthesis of dianhydrides is somewhat more complex than that of diamines and until recent time pyromellitic dianhydride (PMDA) and benzophenone-3,3, 4,4 -tetracarboxylic dianhydride (BTDA) had been the only commercially produced aromatic dianhydrides. Some of the significant commercial products developed recently, are Upilex by UBE Ind. and Ultem by General Electric. The former is based on biphenyl-3,3, 4,4 -tetracarboxylic dianhydride (BPDA) and the latter on 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride or bisphenol A dianhydride (BPA-DA). BPDA is produced by oxidative coupling of inexpensive phthalic acid esters in the presence of palladium catalyst [23, 24]. 

Upilex Type R by UBE Ind. is produced from BPDA and ODA. It is based on a unique combination of the new monomer synthesis described in the preceding section and one step high temperature solution polymerization in a phenolic solvent [42]. High quality films and fibers can be produced from the solution because a water forming reaction is not involved [43]. The polymers produced by such a process have a completely imidized structure and provide for superior properties than polymers prepared by solid state imidization of polyamic acids. For example long term oxidative and hydrolytic stabilities and retention of electrical properties are substantially better. 

Upilex S Type which is primarily composed of BPDA and p-phenylenediamine was reported to have a very good dimensional stability and very low CLTE [114]. 

Polymer Films. Samples of DuPont KAPT0N, Mitsubishi N0VAX, Ube UPILEX-S and General Electric ULTEM films were obtained from commercial sources. Chemical structures of the commercial polymers, as understood from the literature, are shown below. 

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