POLY(BIPHENYL ETHER SULFONE) RESIN, PRODUCTION METHOD THEREFOR, AND MELT-MOLDED ARTICLE

Abstract

The present invention relates to a poly(biphenyl ether sulfone) resin substantially comprising a repeating structure of the following formula (1), and having a spin-lattice relaxation time T.sub.IL of a long component of 24 s or more, which is calculated from decay of a signal intensity I (τ) corresponding to a chemical shift of 129 ppm by acquiring a .sup.13C-NMR spectrum by a Torchia pulse sequence using an NMR device for solid sample measurement and changing a value of a waiting time τ in the pulse sequence,

##STR00001## wherein n represents an integer of 1 or more.

Claims

1. A poly(biphenyl ether sulfone) resin substantially comprising a repeating structure of the following formula (1) and having a spin-lattice relaxation time T.sub.IL, calculated from the following <Method for calculating spin-lattice relaxation time T.sub.IL> of 24 s or more, ##STR00011## wherein n represents an integer of 1 or more; <Method for calculating spin-lattice relaxation time T.sub.IL> The spin-lattice relaxation time T.sub.IL of a long component is calculated from decay of a signal intensity I (τ) corresponding to a chemical shift of 129 ppm by acquiring a .sup.13C-NMR spectrum of said poly(biphenyl ether sulfone) resin by a Torchia pulse sequence using an NMR device for solid sample measurement and changing a value of a waiting time τ in said pulse sequence.

2. A method for producing a poly(biphenyl ether sulfone) resin substantially comprising a repeating structure of the following formula (1), the method comprising allowing a polycondensation reaction of a 4,4′-dihalogenodiphenyl sulfone compound and 4,4′-dihydroxybiphenyl in an aprotic polar solvent, ##STR00012## wherein n represents an integer of 1 or more, and said polycondensation reaction is carried out so that a calculated mass A of a poly(biphenyl ether sulfone) resin to be obtained by said polycondensation reaction and a charged mass B of said aprotic polar solvent satisfy the following formula (5):
35≤A×100÷(A+B)≤44  (5).

3. The method for producing a poly(biphenyl ether sulfone) resin according to claim 2, wherein said 4,4′-dihalogenodiphenyl sulfone compound is 4,4′-dichlorodiphenyl sulfone.

4. A melt-molded article comprising the poly(biphenyl ether sulfone) resin according to claim 1.

Description

EXAMPLES

[0080] Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited in any way by the examples shown below.

<Measurement of Mn and Mw of Poly(Biphenyl Ether Sulfone) Resin, Calculation of Mw/Mn>

[0081] The polystyrene equivalent mass average molecular weight (Mw), number average molecular weight (Mn) and polydispersity (Mw/Mn) of a poly(biphenyl ether sulfone) resin were determined by GPC measurement under the following measurement conditions.

[Measurement Conditions]

[0082] Sample: 0.025 g of poly(biphenyl ether sulfone) resin to be measured was added to 10 mL of an N,N-dimethylformamide solution containing 10 mM lithium bromide.

[0083] Sample injection volume: 10 μL

[0084] Column (stationary phase): Two columns of “TSKgel SuperHZM-M (base material: styrene divinylbenzene)” (4.6 mm)×150 mm) manufactured by Tosoh Corporation were connected in series.

[0085] Column temperature: 40° C.

[0086] Eluent (mobile phase): N,N-dimethylformamide containing 10 mM lithium bromide

[0087] Eluent flow rate: 0.35 mL/min

[0088] Detector: UV detector

[0089] Detection wavelength: 300 nm

[0090] Molecular weight standard: polystyrene

<Calculation of .sup.13C-NMR Relaxation Time T.sub.IL>

[0091] The relaxation time T.sub.IL of .sup.13C-NMR of the poly(biphenyl ether sulfone) resin to be measured was calculated from decay of a signal intensity I (τ) corresponding to a chemical shift of 129 ppm corresponding to .sup.13C of the main chain of the poly(biphenyl ether sulfone) resin by acquiring a .sup.13C-NMR spectrum by a Torchia pulse sequence using an NMR device for solid sample measurement and changing a value of a waiting time τ in the pulse sequence.

[0092] The obtained signal strength I (τ) can be expressed by the following formula (F1), and the relaxation time T.sub.IL was calculated from the fitting using the least squares method by plotting I(τ) against time τ. The unit of the relaxation time T.sub.IL is seconds [s].

I(τ)=a.sub.1×exp(−τ/T.sub.IS)+a.sub.2×exp(−τ/T.sub.IL)  (F1)

[0093] [In the formula, a.sub.1 and a.sub.2 represent coefficients calculated so that the sum of the first term and the second term in the formula (F1) by fitting by the least squares method is equivalent to the signal intensity I(τ) obtained by the measurement. T.sub.IS and T.sub.IL represent relaxation times calculated by fitting by the least squares method so that T.sub.IS<T.sub.IL.]

<Solid .SUP.13.C-NMR Measurement>

[0094] In the examples, the solid .sup.13C-NMR measurement for calculating the relaxation time T.sub.IL was performed under the following measurement conditions using a method of observing the magnetization of .sup.13C after transferring the magnetization of .sup.1H to .sup.13C.

[0095] Measuring device: PS400WB (manufactured by Varian, Inc.)

[0096] Static magnetic field strength: 9.4 Tesla (resonant frequency: 400 MHz (.sup.1H))

[0097] Magic angle spinning: 10 kHz (10,000 rotations per second)

[0098] Contact time: 2 ms

[0099] Repetition time: 6 s

[0100] Number of integrations: 1,024 times

[0101] Sample: powder form (about 15 mg)

[0102] Temperature: 25° C.

[0103] Chemical shift reference material: adamantane

[0104] Waiting time τ: 0.02 s, 0.054 s, 0.15 s, 0.4 s, 1.09 s, 2.98 s, 8.1 s, 22 s

<Impact Resistance Test>

[0105] A poly(biphenyl ether sulfone) resin to be measured was placed in a cavity portion of an SUS spacer having a thickness of 2 mm and sandwiched between a pair of flat aluminum plates. Furthermore, the entirety thereof was sandwiched between a pair of flat steel plates and preheated at 305° C. for 13 minutes in a hot press machine, and was then heated and compressed for 2 minutes at a pressure which was sufficient for fusing the poly(biphenyl ether sulfone) resin to make the thickness the same as that of the SUS spacer. Then, the resultant was cooled with a cooling press machine set at 25° C. to obtain a plate having a thickness of 1.9 mm. The obtained molded plate was cut into a test piece having dimensions of 70 mm in length, 10 mm in width and 19 mm in thickness and having a notch with a tip radius of 0.25 mm and a depth of 5 mm in a central portion, and the Izod impact resistance [J/m] was measured in accordance with ASTM D256.

<Thermal Aging Test>

[0106] The test piece was molded, and then placed in an oven at 180° C. and left to stand for 24 hours, and the resultant was used as a test piece after thermal annealing in an impact resistance test. The impact resistance test was conducted in accordance with ASTM D256.

<Production of Poly(Biphenyl Ether Sulfone) Resin>

Example 1

[0107] Mixed were 100.0 parts by mass (1 molar ratio) of 4,4′-dihydroxybiphenyl, 159.0 parts by mass (1.031 molar ratio) of 4,4′-dichlorodiphenyl sulfone and 308.5 parts by mass of diphenyl sulfone, in a polymerization vessel equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser attached with a receiver at the tip, and the temperature was raised to 180° C. while causing nitrogen gas to flow into the system. Added was 76.4 parts by mass (1.030 molar ratio) of potassium carbonate to the obtained mixed solution, and then the temperature was gradually raised to 290° C. and the reaction was further carried out at 290° C. for 4.5 hours. Subsequently, the obtained reaction mixture solution was cooled to room temperature to be solidified, finely pulverized, and then washed several times by decantation and filtration using warm water and a mixed solvent of acetone and methanol. The obtained solid was heated and dried at 150° C. to obtain a poly(biphenyl ether sulfone) resin of Example 1. Table 1 shows the polymerization concentration, mass average molecular weight Mw and polydispersity Mw/Mn, the relaxation time T.sub.IL measured using the powder obtained as a polymerization product, and the evaluation results of the impact resistance test and thermal aging test.

[0108] It should be noted that when determining the polymerization concentration in Example 1, the calculated mass A of the poly(biphenyl ether sulfone) resin obtained by the polycondensation reaction was determined as the amount (219.8 parts by mass) obtained by subtracting the mass of hydrogen halide (2×36.46×0.537) corresponding to twice the number of moles of the charged mass of 4,4′-dihydroxybiphenyl from the sum (259.0 parts by mass) of the charged mass (159.0 parts by mass) of the 4,4′-dihalogenodiphenyl sulfone compound and the charged mass (100.0 parts by mass) of 4,4′-dihydroxybiphenyl. The polymerization concentration was calculated from the formula: 219.8×100=(219.8+308.5).

[0109] The poly(biphenyl ether sulfone) resin of Example 1 had a relaxation time T.sub.IL of 24 s or more, and the melt-molded article obtained from the poly(biphenyl ether sulfone) resin exhibited excellent impact resistance and had little change in impact resistance before and after thermal annealing, that is, was less susceptible to thermal aging.

Example 2

[0110] A poly(biphenyl ether sulfone) resin of Example 2 was obtained under the same conditions as in Example 1 except that the amount of diphenyl sulfone was 308.9 parts by mass and the amount of potassium carbonate was 76.1 parts by mass (1.025 molar ratio), and the reaction time at 290° C. was 4 hours. Table 1 shows the polymerization concentration, mass average molecular weight Mw and polydispersity Mw/Mn, the relaxation time T.sub.IL measured using the powder obtained as a polymerization product, the relaxation time T.sub.IL measured using the powder obtained by freezing and crushing the test piece formed during the impact resistance test, and the evaluation results of the impact resistance test and thermal aging test.

[0111] Freezing and crushing were carried out under the following conditions by filling a stainless steel container with a sample.

[0112] Freeze crusher: Freezer Mill 6770 manufactured by SPEX SamplePrep, LLC.

[0113] Temperature: liquid nitrogen temperature

[0114] Crushing time: 3 minutes

[0115] The poly(biphenyl ether sulfone) resin of Example 2 had a relaxation time T.sub.IL of 24 s or more, and the relaxation time T.sub.IL of the melt-molded article obtained from the poly(biphenyl ether sulfone) resin was also 24 s or more. That is, it was confirmed that the relaxation time TH, measured while the poly(biphenyl ether sulfone) resin of Example 2 was in a state of the powder as a polymerization product and the relaxation time T.sub.IL measured for the melt-molded article obtained by producing pellets from the polymerized powder by melt extrusion molding, followed by further melt molding were substantially the same. The above melt-molded article exhibited excellent impact resistance and had little change in impact resistance before and after thermal annealing, that is, was less susceptible to thermal aging.

Example 3

[0116] A poly(biphenyl ether sulfone) resin of Example 3 was obtained under the same conditions as in Example 1 except that the amount of 4,4′-dichlorodiphenyl sulfone was 158.8 parts by mass (1.030 molar ratio), the amount of diphenyl sulfone was 306.8 parts by mass and the amount of potassium carbonate was 78.0 parts by mass (1.050 molar ratio), and the reaction time at 290° C. was 4 hours. Table 1 shows the polymerization concentration, mass average molecular weight Mw and polydispersity Mw/Mn, and the relaxation time T.sub.IL measured using the powder obtained as a polymerization product. The poly(biphenyl ether sulfone) resin of Example 3 had a relaxation time T.sub.IL of 24 s or more.

Comparative Example 1

[0117] Mixed were 100.0 parts by mass (1 molar ratio) of 4,4′-dihydroxybiphenyl, 159.0 parts by mass (1.031 molar ratio) of 4,4′-dichlorodiphenyl sulfone and 213.4 parts by mass of diphenyl sulfone, in a polymerization vessel equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser attached with a receiver at the tip, and the temperature was raised to 180° C. while causing nitrogen gas to flow into the system. Added was 77.2 parts by mass (1.040 molar ratio) of potassium carbonate to the obtained mixed solution, and then the temperature was gradually raised to 290° C. and the reaction was further carried out at 290° C. for 4 hours. Subsequently, the obtained reaction mixture solution was cooled to room temperature to be solidified, finely pulverized, and then washed several times by decantation and filtration using warm water and a mixed solvent of acetone and methanol. The obtained solid was heated and dried at 150° C. to obtain a poly(biphenyl ether sulfone) resin of Comparative Example 1. Table 1 shows the polymerization concentration, mass average molecular weight Mw and polydispersity Mw/Mn, the relaxation time T.sub.IL measured using the powder obtained as a polymerization product, the relaxation time T.sub.IL measured using the powder obtained by freezing and crushing the test piece formed during the impact resistance test, and the evaluation results of the impact resistance test and thermal aging test.

[0118] The poly(biphenyl ether sulfone) resin of Comparative Example 1 had a relaxation time T.sub.IL of less than 24 s, and the relaxation time T.sub.IL of the melt-molded article obtained by melt molding the poly(biphenyl ether sulfone) resin was also less than 24 s. That is, it was confirmed that the relaxation time T.sub.IL measured while the poly(biphenyl ether sulfone) resin of Comparative Example 1 was in a state of the powder as a polymerization product and the relaxation time T.sub.IL measured for the melt-molded article obtained by producing pellets from the polymerized powder by melt extrusion molding, followed by further melt molding were substantially the same. The above melt-molded article exhibited a significant reduction in impact resistance when thermal annealing was performed, that is, was susceptible to thermal aging.

Comparative Example 2

[0119] A poly(biphenyl ether sulfone) resin of Comparative Example 2 was obtained under the same conditions as in Comparative Example 1 except that the amount of diphenyl sulfone was 214.9 parts by mass and the amount of potassium carbonate was 75.7 parts by mass (1.020 molar ratio). Table 1 shows the polymerization concentration, mass average molecular weight Mw and polydispersity Mw/Mn, the relaxation time T.sub.IL measured using the powder obtained as a polymerization product, and the evaluation results of the impact resistance test and thermal aging test.

[0120] The poly(biphenyl ether sulfone) resin of Comparative Example 2 had a relaxation time T.sub.IL of less than 24 s, and the melt-molded article obtained by melt molding the poly(biphenyl ether sulfone) resin exhibited a significant reduction in impact resistance when thermal annealing was performed, that is, was susceptible to thermal aging.

TABLE-US-00001 TABLE 1 T.sub.1 L measured Impact using powder T.sub.1 L measured by resistance Thermal DCDPS/ K.sub.2CO.sub.3/ Polymerization obtained as freezing and test before aging test BP molar BP molar concentration polymerization crushing molded thermal after thermal Examples ratio ratio [%] Mw Mw/Mn product [s] article [s] annealing [J/m] annealing [J/m] Ex. 1 1.031 1.030 42 70900 4.7 25.8 — 649 614 Ex. 2 1.031 1.025 42 69400 4.7 26.2 25.0 623 796 Ex. 3 1.030 1.050 42 68300 4.7 25.2 — — — Comp. Ex. 1 1.031 1.040 51 71500 4.9 22.8 21.5 519 30 Comp. Ex. 2 1.031 1.020 51 60000 4.7 22.4 — 233 50 DCDPS: 4,4′-dichlorodiphenyl sulfone BP: 4,4′-dihydroxybiphenyl

[0121] The poly(biphenyl ether sulfone) resins of Examples 1 to 3 were produced by adjusting the polymerization concentration defined from the calculated mass A of the poly(biphenyl ether sulfone) resin to be obtained by the polycondensation reaction and the charged mass B of the aprotic polar solvent by the formula: [A×100÷(A+B)] to a constant concentration of 35% or more and 44% or less. The poly(biphenyl ether sulfone) resins of the examples had relaxation times TH of 24 s or more, and the melt-molded articles obtained from these poly(biphenyl ether sulfone) resins exhibited excellent impact resistance and had little change in impact resistance before and after thermal annealing, that is, were less susceptible to thermal aging.

[0122] On the other hand, the poly(biphenyl ether sulfone) resins of the comparative examples produced under the conditions in which the polymerization concentration defined by the formula: [A×100÷(A+B)] exceeded 44% had relaxation times T.sub.IL of less than 24 s despite having about the same mass average molecular weights as those of the poly(biphenyl ether sulfone) resins of the examples. Further, the melt-molded articles obtained from the poly(biphenyl ether sulfone) resins of the comparative examples were inferior in impact resistance to the melt-molded articles obtained from the poly(biphenyl ether sulfone) resins of the examples, and significant reductions in impact resistance were observed after thermal annealing.

INDUSTRIAL APPLICABILITY

[0123] The melt-molded article obtained from the poly(biphenyl ether sulfone) resin of the present invention exhibits excellent impact resistance and has little change in impact resistance before and after thermal annealing, that is, it is less susceptible to thermal aging. Such melt-molded articles can be expected to be used in a wide range of applications such as electrical/electronic materials, automobile parts, medical materials, heat resistant coating materials, separation membranes, or resin joints, especially in various applications that are expected to be used in a high temperature atmosphere.