NO143826B - DIAGNOSTIZING AGENT, PRINCIPLES IN THE FORM OF A TEST STRIP, FOR DETECTION OF ACET-ACETIC ACID IN BIOLOGICAL LIQUIDS - Google Patents

DIAGNOSTIZING AGENT, PRINCIPLES IN THE FORM OF A TEST STRIP, FOR DETECTION OF ACET-ACETIC ACID IN BIOLOGICAL LIQUIDS Download PDF

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Publication number
NO143826B
NO143826B NO742323A NO742323A NO143826B NO 143826 B NO143826 B NO 143826B NO 742323 A NO742323 A NO 742323A NO 742323 A NO742323 A NO 742323A NO 143826 B NO143826 B NO 143826B
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Norway
Prior art keywords
diagnostizing
acet
agent
principles
detection
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NO742323A
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Norwegian (no)
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NO742323L (en
NO143826C (en
Inventor
Yasunao Ogawa
Yukio Yonetani
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Shionogi & Co
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Publication of NO742323L publication Critical patent/NO742323L/no
Publication of NO143826B publication Critical patent/NO143826B/en
Publication of NO143826C publication Critical patent/NO143826C/en

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/50Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
    • G01N33/64Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving ketones
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T436/00Chemistry: analytical and immunological testing
    • Y10T436/20Oxygen containing
    • Y10T436/200833Carbonyl, ether, aldehyde or ketone containing

Description

Fremgangsmåte til å stabilisere polyoxymethylener rnot varme. Process for stabilizing polyoxymethylenes without heat.

Foreliggende oppfinnelse angår polyoxymethylener som er stabilisert mot varme, hvilke er nyttige termoplastiske materialer, samt deres fremstilling ved acetylering av polymerens ende-hydroxy-grupper med methylenglycoldiacetat. The present invention relates to polyoxymethylenes which are stabilized against heat, which are useful thermoplastic materials, as well as their production by acetylating the terminal hydroxy groups of the polymer with methylene glycol diacetate.

Oppfinnelsen skaffer en fremgangsmåte til fremstilling av polyoxymethylener som er stabilisert mot varme, hvilken fremgangsmåte omfatter transforestring av polyoxymethylenene med overskudd av methylenglycoldiacetat ved en temperatur mellom 170 og 210° C. Det foretrukne vektforhold mellom polymer og acetyle-ringsmiddel er fra 1:5 til 1:15, og de nød-vendige reaksjonstider er mindre enn 3 timer. The invention provides a method for the production of polyoxymethylenes that are stabilized against heat, which method comprises transesterification of the polyoxymethylenes with an excess of methylene glycol diacetate at a temperature between 170 and 210° C. The preferred weight ratio between polymer and acetylating agent is from 1:5 to 1 :15, and the necessary reaction times are less than 3 hours.

En hurtig og fullstendig oppløsning av polymeren inntreffer ved disse temperatu-rer, og en hurtig acetylering ved transforestring bevirkes. A rapid and complete dissolution of the polymer occurs at these temperatures, and a rapid acetylation by transesterification is effected.

Det er funnet at methylenglycoldiacetat er å foretrekke som acetyleringsimiddel fremfor eddiksyreanhydrid da spaltningen av den behandlede polymer herved blir mindre. Dette illustreres i tabell 1, hvor der er gjengitt eksempler på acetylering ved bruk av begge aoetyleringsmidler og de samme eksperimentelle betingelser. It has been found that methylene glycol diacetate is preferable as an acetylating agent to acetic anhydride as the cleavage of the treated polymer is thereby reduced. This is illustrated in table 1, where examples of acetylation using both aoethylating agents and the same experimental conditions are reproduced.

For de nevnte forsøk ble der fremstillet produkter med varierende omfang av mo-lekylkompleksene. Noen av produktene ble fremstillet ved polymeriseringsmetoden i gassfase ved hjelp av en topokjemisk reaksjon som beskrevet i italiensk patent nr. 626 461 (produkt 3 og 4) og andre ved poly-merisering i vandig oppløsning som beskrevet i italiensk patent 646 437 (produkt 1 og 2). De reduserte viskositeter (j.iS|l/C) ble målt i dimethylformamid ved 150° C. For the aforementioned experiments, products with varying extents of the molecular complexes were produced. Some of the products were produced by the polymerization method in the gas phase using a topochemical reaction as described in Italian patent no. 626 461 (product 3 and 4) and others by polymerization in aqueous solution as described in Italian patent 646 437 (product 1 and 2). The reduced viscosities (j.iS|l/C) were measured in dimethylformamide at 150°C.

Ved betraktning av de tabellariserte data ser man at produktene stabilisert med methylenglycoldiacetat oppviser en viskositet som er 5—30 pst. høyere enn viskositeten av de produkter som er stabilisert med eddiksyreanhydrid, og at jo høyere viskositeten er, desto større er for-bedringen. When considering the tabulated data, it can be seen that the products stabilized with methylene glycol diacetate exhibit a viscosity that is 5-30 per cent higher than the viscosity of the products stabilized with acetic anhydride, and that the higher the viscosity, the greater the improvement.

Et ytterligere bevis for at methylenglycoldiacetat er et mer skånsomt reagens og i mindre grad bevirker avbyggende bi-reaksjoner i den polymere illustreres i tabell 2, hvori verdiene av de reduserte viskositeter for to forskjellige polymere som er stabilisert med de to reagenser ved 170° C, er gjengitt efter økende tidsrom. Further proof that methylene glycol diacetate is a gentler reagent and causes less degradative side-reactions in the polymer is illustrated in Table 2, in which the values of the reduced viscosities for two different polymers stabilized with the two reagents at 170°C, are reproduced after increasing time periods.

Utbyttet av produktene stabilisert med methylenglycoldiacetat forbedres bemer-kelsesverdig når stabiliseringen bevirkes i nærvær av små mengder, fra 0,5 til 3 pst. av keten. Forbedrede utbytter av de ace-tylerte produkter oppnåes også når eddiksyreanhydrid tilsettes i mengder fra 3 til 30 pst. The yield of the products stabilized with methylene glycol diacetate is remarkably improved when the stabilization is effected in the presence of small amounts, from 0.5 to 3 percent, of the ketene. Improved yields of the acetylated products are also obtained when acetic anhydride is added in amounts from 3 to 30 per cent.

Utbyttene økes når begge midler be-nyttes sammen. Dette illustreres i tabellene 3, 4 og 5, hvori produkt 2 i tabell 1 er an-vendt. The dividends are increased when both funds are used together. This is illustrated in tables 3, 4 and 5, in which product 2 in table 1 is used.

For i praksis å utføre fremgangsmåten ifølge foreliggende oppfinnelse behandles et polyoxymethylendihydroxyd fremstillet ved en hvilkensomhelst egnet fremgangsmåte og av en hvilkensomhelst polymeri-seringsgrad, med ca. 10 vektsdeler methylenglycoldiacetat eller med blandinger der-av med de lavere ledd av serien av poly-oxymethylendiacetat-homologe og oppvarmes til 170—175° C i en autoklav som vip-pes eller omrøres. For produkter med me-get høy molekylvekt, som ikke er fullstendig oppløselige ved 170° C, utføres stabiliseringen ved en høyere temperatur, opp til 200—210° C. Temperaturen bibeholdes i 5—15 minutter fra det tidspunkt da produktet er fullstendig oppløst. Reaksjons-blandingen får avkjøles til romtemperatur, sentrifugeres så, vaskes dersom dette øn-skes, med en inert organisk væske, og tør-res tilslutt fortrinsvis under vakuum. In order to practically carry out the method according to the present invention, a polyoxymethylene dihydroxide produced by any suitable method and of any degree of polymerization is treated with approx. 10 parts by weight of methylene glycol diacetate or with mixtures thereof with the lower links of the series of polyoxymethylene diacetate homologues and heated to 170-175° C in an autoclave which is tilted or stirred. For products with a very high molecular weight, which are not completely soluble at 170° C, the stabilization is carried out at a higher temperature, up to 200-210° C. The temperature is maintained for 5-15 minutes from the time when the product is completely dissolved. The reaction mixture is allowed to cool to room temperature, then centrifuged, washed, if desired, with an inert organic liquid, and finally dried preferably under vacuum.

Utførelsen skjer under de samme betingelser når methylengiycoldiacetatene som anvendes inneholder keten og/eller eddiksyreanhydrid. The execution takes place under the same conditions when the methylene glycol diacetates used contain ketene and/or acetic anhydride.

Den gjenvundne væske beholder egen-skapene til acetyleringsmidlet. For å unn- gå opphopning i dette av eddiksyre dannet ved hydrolyse av acetater, forårsaket av vannet som utgjør endegruppene av hvert ledd av serien av polyoxyimethylen-diacetat-homologe, kan en tilsvarende mengde keten tilsettes f. eks. periodevis. The recovered liquid retains the properties of the acetylating agent. In order to avoid accumulation in this of acetic acid formed by hydrolysis of acetates, caused by the water which forms the end groups of each member of the series of polyoxyimethylene diacetate homologues, a corresponding amount of ketene can be added, e.g. periodically.

Eddiksyreanhydrid må også tilsettes periodevis for å unngå en uønsket opphopning av høyere ledd i polyoxymethylendi-acetatserien dannet ved addisjon av for-maldehyd som avspaltes fra produktene som stabiliseres: Acetic anhydride must also be added periodically to avoid an unwanted accumulation of higher links in the polyoxymethylene diacetate series formed by the addition of formaldehyde which splits off from the products that are stabilized:

Eksempel 1. 30 g polyoxymethylendihydroxyd, fremstillet ved topokjemisk reaksjon ifølge fremgangsmåten beskrevet 1 italiensk patent nr. 626 461, og 300 g methylenglycoldiacetat med kokepunkt i området mellom 166 og 173° C, anbringes for et tidsrom av 20 minutter i en glassautoklav. Ved produk-tets koketemperatur oppløses dette innen 10 minutter. Det får avkjøles langsomt til romtemperatur i løpet av ca. 2 timer. Det filtreres under vakuum og vaskes gjen-tagne ganger med benzen, idet der anvendes en total benzenmengde tilsvarende den dobbelte vekt av polyoxymethylendi-hydroxydet. 28,5 g tørt produkt erholdes, nemlig 95 pst. av det teoretiske. Example 1. 30 g of polyoxymethylene dihydroxide, produced by topochemical reaction according to the method described in Italian patent no. 626 461, and 300 g of methylene glycol diacetate with a boiling point in the range between 166 and 173° C, are placed for a period of 20 minutes in a glass autoclave. At the product's boiling temperature, this dissolves within 10 minutes. It is allowed to cool slowly to room temperature during approx. 2 hours. It is filtered under vacuum and washed repeatedly with benzene, using a total amount of benzene corresponding to twice the weight of the polyoxymethylene dihydroxide. 28.5 g of dry product is obtained, namely 95 per cent of the theoretical.

Den termiske stabilitet av dette og andre produkter erholdt ved fremgangsmåten ifølge foreliggende oppfinnelse ble målt ved oppvarmning av ca. 0,5 g av produktet ved 215° C i 30 minutter. Resulta-tene er uttrykt ved den kinetiske depoly-merisasjonskonstant (K^l5) som er definert som vekttapet pr. minutt beregnet pr. 100 g utgangspolymer. For dette produkt ble K.,l5 funnet å være 0,1. Den reduserte viskositet målt i dimethylformamid ved 150° C i 0,5 pst. konsentrasjon hie funnet å være 3,4. The thermal stability of this and other products obtained by the method according to the present invention was measured by heating approx. 0.5 g of the product at 215° C for 30 minutes. The results are expressed by the kinetic depolymerization constant (K^l5), which is defined as the weight loss per minute calculated per 100 g of starting polymer. For this product, K 15 was found to be 0.1. The reduced viscosity measured in dimethylformamide at 150°C in 0.5% concentration was found to be 3.4.

Eksempel 2. Example 2.

20 g polyoxymethylendihydroxyd, fremstillet ved fremgangsmåten beskrevet i italiensk patent nr. 646 437, behandles med 200 g methylenglycoldiacetat under samme betingelser som i eksempel 1 hva angår både stabiliseringsreaksjonen og de etterfølgende vaske- og tørreoperasjoner. 15,6 g tørt produkt erholdes, hvilket tilsvarer et utbytte av acetylert produkt på 78 20 g of polyoxymethylene dihydroxide, produced by the method described in Italian patent no. 646 437, is treated with 200 g of methylene glycol diacetate under the same conditions as in example 1 as regards both the stabilization reaction and the subsequent washing and drying operations. 15.6 g of dry product is obtained, which corresponds to a yield of acetylated product of 78

pst. For dette produkt ble de følgende ver-dier oppnådd: K. >iri = 0,05; redusert viskositet = 0,93. wt. For this product the following values were obtained: K. >iri = 0.05; reduced viscosity = 0.93.

Eksempel 3. 30 g av produktet fremstillet ved fremgangsmåten beskrevet i italiensk patent nr. 626 461 og 300 g methylenglycoldiacetat inneholdende i oppløsning de første ledd av den homologe serie av poiy-oxymethylendlacetater, hvori antall oxy-methylengrupper er større enn 1 og mindre enn 10, og som derfor har et kokepunkt ved 2 rnm i området mellom 45 og 120° C, oppvarmes i en glassautoklav ved 170°C for et tidsromav20 minutter. Denne temperatur bibeholdes i 30 minutter, der-efter avkjøles autøklaven og produktet filtreres og tørres som i de foregående eksempler. 26,4 g av polymeren erholdes, hvilket tilsvarer et utbytte på 88 pst. K.,,.-= 0,08. Redusert viskositet, målt som an-gitt i de foregående eksempler, var 1,05. i Example 3. 30 g of the product produced by the method described in Italian patent no. 626 461 and 300 g of methylene glycol diacetate containing in solution the first members of the homologous series of polyoxymethylene acetates, in which the number of oxymethylene groups is greater than 1 and less than 10 , and which therefore has a boiling point at 2 rnm in the range between 45 and 120° C, is heated in a glass autoclave at 170° C for a period of 20 minutes. This temperature is maintained for 30 minutes, after which the autoclave is cooled and the product is filtered and dried as in the previous examples. 26.4 g of the polymer is obtained, which corresponds to a yield of 88 percent K.,,.-= 0.08. Reduced viscosity, measured as indicated in the previous examples, was 1.05. in

Claims (3)

1. Fremgangsmåte til fremstilling av polyoxymethylener som er stabilisert mot varme, karakterisert ved at et poly-oxymethylen trans-forestres medoverskudd av methylenglycoldiacetat ved en temperatur mellom 170 og 210° C.1. Process for the production of polyoxymethylenes that are stabilized against heat, characterized in that a polyoxymethylene is trans-esterified with an excess of methylene glycol diacetate at a temperature between 170 and 210°C. 2. Fremgangsmåte ifølge påstand 1, karakterisert ved at den utføres i nærvær av 0,5—3 vektpst. keten.2. Method according to claim 1, characterized in that it is carried out in the presence of 0.5-3 wt. the chain. 3. Fremgangsmåte ifølge påstand 1 eller 2, karakterisert ved at den ut-føres i nærvær av 3—30 vektpst. eddiksyreanhydrid.3. Method according to claim 1 or 2, characterized in that it is carried out in the presence of 3-30 wt. acetic anhydride.
NO742323A 1973-11-08 1974-06-26 DIAGNOSTIZING AGENT, PRINCIPLES IN THE FORM OF A TEST STRIP, FOR DETECTION OF ACET-ACETIC ACID IN BIOLOGICAL LIQUIDS NO143826C (en)

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US (1) US3880590A (en)
JP (1) JPS5143796B2 (en)
BE (1) BE816926A (en)
CA (1) CA1021237A (en)
CH (1) CH587491A5 (en)
DE (1) DE2432753C3 (en)
DK (1) DK142296B (en)
ES (1) ES427803A1 (en)
FR (1) FR2250999B1 (en)
GB (1) GB1451268A (en)
IT (1) IT1016633B (en)
NL (1) NL162478C (en)
NO (1) NO143826C (en)
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US5071769A (en) * 1986-12-22 1991-12-10 Abbott Laboratories Method and device for ketone measurement
US4970172A (en) * 1986-12-22 1990-11-13 Abbott Laboratories Method and device for ketone measurements
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US6149865A (en) * 1997-07-07 2000-11-21 Teco Diagnostics, Inc. Test strips for the determination of the ionic strength or specific gravity of an aqueous sample
US5922283A (en) * 1997-07-07 1999-07-13 Teco Diagnostics Test strips for the determination of the ionic strength or specific gravity of an aqueous sample
US6541216B1 (en) 1999-12-22 2003-04-01 Roche Diagnostics Corporation Amperometric biosensor test strip
US6603403B2 (en) 2000-12-12 2003-08-05 Kimberly-Clark Worldwide, Inc. Remote, wetness signaling system
US6583722B2 (en) 2000-12-12 2003-06-24 Kimberly-Clark Worldwide, Inc. Wetness signaling device
US7695975B2 (en) * 2005-06-23 2010-04-13 Siemens Healthcare Diagnostics Inc. Detection of adulterated samples
AU2013263421A1 (en) * 2012-05-15 2014-12-04 Invoy Technologies, Llc Method and apparatus for analyzing acetone in breath
EP3757573A4 (en) * 2018-02-23 2021-08-25 Sysmex Corporation Specimen for detecting ketone bodies in urine

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US2186902A (en) * 1939-04-07 1940-01-09 Lilly Co Eli Urine acetone test
US2362478A (en) * 1941-12-24 1944-11-14 Denver Chemical Mfg Company Reagent for testing for acetone
US2509140A (en) * 1948-03-02 1950-05-23 Miles Lab Test reagent composition
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US2990253A (en) * 1959-05-21 1961-06-27 Miles Lab Diagnostic composition
NL296257A (en) * 1962-08-06
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FR2250999B1 (en) 1977-10-07
SE7408488L (en) 1975-05-09
DE2432753A1 (en) 1975-05-15
CA1021237A (en) 1977-11-22
DE2432753C3 (en) 1981-09-10
DK142296B (en) 1980-10-06
NL7410509A (en) 1975-05-12
NL162478C (en) 1980-05-16
BE816926A (en) 1974-10-16
CH587491A5 (en) 1977-05-13
NO742323L (en) 1975-06-02
JPS5143796B2 (en) 1976-11-24
JPS5078394A (en) 1975-06-26
US3880590A (en) 1975-04-29
SE397733B (en) 1977-11-14
DE2432753B2 (en) 1981-01-22
DK336474A (en) 1975-07-14
ES427803A1 (en) 1977-02-01
IT1016633B (en) 1977-06-20
NO143826C (en) 1981-04-15
FR2250999A1 (en) 1975-06-06
DK142296C (en) 1981-03-02
AU7061474A (en) 1976-01-08
GB1451268A (en) 1976-09-29
NL162478B (en) 1979-12-17

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