TERMINALLY MODIFIED POLYBUTADIENE, RESIN COMPOSITION FOR METAL-CLAD LAMINATES, PREPREG, AND METAL-CLAD LAMINATE

Abstract

Provided is a novel resin composition for a metal-clad laminate, with which a metal-clad laminate having excellent adhesion with a metal foil, solder heat resistance, insulation and the like can be produced. A terminally modified polybutadiene contained in the resin composition for a metal-clad laminate according to the present invention has a structure of formula (III) on each of both terminals of a polybutadiene comprising a repeating unit of formula (I) and a repeating unit of formula (II), wherein a proportion of the repeating unit of formula (I) in all the repeating units is 70 to 99% by mol.

##STR00001##

Claims

1. A terminally modified polybutadiene, comprising: a polybutadiene comprising a repeating unit of formula (I): ##STR00008## and a repeating unit of formula (II):
CH.sub.2—HC═CH—CH.sub.2  (II) wherein a proportion of the repeating unit of formula (I) in all the repeating units is 70 to 99% by mol; and a structure of formula (III) on each of both terminals of the polybutadiene: ##STR00009## (wherein R.sup.1, R.sup.2 and R.sup.3 each independently represent an alkoxy group, an aryloxy group, an alkyl group or an aryl group; X represents a linkage group; and * represents a bonding site; provided that at least one of R.sup.1, R.sup.2 and R.sup.3 is an alkoxy group or an aryloxy group).

2. The terminally modified polybutadiene according to claim 1, wherein the terminally modified polybutadiene has a weight-average molecular weight (Mw) of 1,000 to 100,000.

3. The terminally modified polybutadiene according to claim 1, wherein the terminally modified polybutadiene has a molecular weight distribution (Mw/Mn) of 1.00 to 3.00.

4. A resin composition for a metal-clad laminate, comprising the terminally modified polybutadiene according to claim 1.

5. The resin composition for the metal-clad laminate according to claim 4, further comprising an organic peroxide.

6. The resin composition for the metal-clad laminate according to claim 5, wherein the organic peroxide is contained in 1 to 5 parts by weight with respect to 100 parts by weight of the terminally modified polybutadiene.

7. A prepreg, comprising a base material impregnated with the resin composition for the metal-clad laminate according to claim 4.

8. A metal-clad laminate, being produced by laminating and forming the prepreg according to claim 7 and a metal foil.

Description

EXAMPLES

[0069] Hereinafter, the present invention will be described in detail by way of Examples, but the present invention is not limited to the scope of the Examples.

Synthesis of Terminally Modified Polybutadienes

Production Example 1

[0070] 100 g of NISSO-PB G-1000 (hydroxyl value: 73.0 mgKOH/g) was put in a 200-mL flask. 24.04 g of 3-isocyanatopropyltrimethoxysilane was added thereto so as to become 0.9 mol time the number of moles corresponding to the hydroxyl value of G-1000. The resultant was heated up to 60° C. under full stirring to be reacted for 12 hours to thereby obtain a terminally modified polybutadiene A. The obtained terminally modified polybutadiene A had a number-average molecular weight (Mn) of 3,200 and a molecular weight distribution (Mw/Mn) of 2.24. Here, the weight-average molecular weight (Mw) and the number-average molecular weight (Mn) were values in terms of molecular weights of standard polystyrenes measured by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent.

Production Example 2

[0071] 100 g of NISSO-PB G-3000 (hydroxyl value: 31.0 mgKOH/g) was put in a 200-mL flask. 10.21 g of 3-isocyanatopropyltrimethoxysilane was added thereto so as to become 0.9 mol time the number of moles corresponding to the hydroxyl value of G-3000. The resultant was heated up to 60° C. under full stirring to be reacted for 12 hours to thereby obtain a terminally modified polybutadiene B. The obtained terminally modified polybutadiene B had a number-average molecular weight (Mn) of 6,700 and a molecular weight distribution (Mw/Mn) of 1.57. Here, the weight-average molecular weight (Mw) and the number-average molecular weight (Mn) were values in terms of molecular weights of standard polystyrenes measured by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent.

Production Example 3

[0072] A both-terminal hydroxyl group-modified 1,4-polybutadiene was synthesized by using a radical initiator, with reference to Polymer Synthesis (Vol. 1), edited by Takeshi Endo, 1.sup.st Edition, Kodansha Ltd., 2010 (in Japanese). The synthesized 1,4-polybutadiene had an Mn of about 5,000, a 1,2-vinyl ratio of about 20% and a hydroxyl value of about 48 mgKOH/g.

[0073] 100 g of the 1,4-polybutadiene (hydroxyl value: 48.0 mgKOH/g) synthesized in the above was put in a 200-mL flask. 15.81 g of 3-isocyanatopropyltrimethoxysilane was added thereto so as to become 0.9 mol time the number of moles corresponding to the hydroxyl value of the 1,4-polybutadiene. The resultant was heated up to 60° C. under full stirring to be reacted for 12 hours to thereby obtain a terminally modified polybutadiene C. The obtained terminally modified polybutadiene C had a number-average molecular weight (Mn) of 6,000 and a molecular weight distribution (Mw/Mn) of 2.10. Here, the weight-average molecular weight (Mw) and the number-average molecular weight (Mn) were values in terms of molecular weights of standard polystyrenes measured by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent.

Fabrication of Metal-Clad Laminates

Example 1

[0074] The terminally modified polybutadiene A, the solvent and the organic peroxide in proportions indicated in Table 1 were mixed to thereby obtain a vanish. A glass cloth was dipped in the vanish to impregnate the glass cloth with the resin. Thereafter, the vanish-impregnated glass cloth was dried at 150° C. for 10 min to thereby obtain a prepreg. The mat surface of a copper foil of 18 μm in thickness was laminated on one surface of the prepreg. Thereafter, the resultant was heated at 195° C. for 120 min under a pressure of 3 MPa to thereby obtain a metal-clad laminate.

TABLE-US-00001 TABLE 1 Example Comparative Example 1 2 1 2 3 4 Terminally modified polybutadiene A 100 — — — — — Terminally modified polybutadiene B — 100 — — — — Terminally modified polybutadiene C — — 100 — — — B-1000 — — — 100 — — B-3000 — — — — 100 — 1,4-Polybutadiene — — — — — 100 Toluene 100 100 100 100 100 100 Dicumyl peroxide 3 3 3 3 3 3

(Dielectric Constant, Dielectric Loss Tangent)

[0075] The dielectric constant and dielectric loss tangent were measured for the resin alone. The dielectric constant and dielectric loss tangent at a measurement frequency of 5 GHz were measured by a probe method. The results are shown in Table 2.

(Peel Strength)

[0076] The peel strength was measured according to JIS C6481. The metal-clad laminate was subjected to a 90° C. peel test of the copper foil to measure the peel strength. The result is shown in Table 2.

(Solder Heat Resistance)

[0077] The solder heat resistance was measured according to JIS C6481. The copper-clad laminate was dipped in a solder at 260° C. for 2 min and the solder heat resistance was evaluated by observing peeling of the copper foil. The case where no peeling occurred was evaluated as “∘”; and the case where peeling occurred, as “x”. The results are shown in Table 2.

Example 2

[0078] Fabrication of a metal-clad laminate, and tests for measurements of the dielectric constant and dielectric loss tangent and for the peel strength and the solder heat resistance, were carried out as in Example 1, except for using a terminally modified polybutadiene B as the resin component. The results are shown in Table 2.

Comparative Example 1

[0079] Fabrication of a metal-clad laminate, and tests for measurements of the dielectric constant and dielectric loss tangent and for the peel strength and the solder heat resistance, were carried out as in Example 1, except for using a terminally modified polybutadiene C as the resin component. The results are shown in Table 2.

Comparative Example 2

[0080] Fabrication of a metal-clad laminate, and tests for measurements of the dielectric constant and dielectric loss tangent and for the peel strength and the solder heat resistance, were carried out as in Example 1, except for using NISSO-PB B-1000, which had no functional group on the terminals, as the resin component. The results are shown in Table 2.

Comparative Example 3

[0081] Fabrication of a metal-clad laminate, and tests for measurements of the dielectric constant and dielectric loss tangent and for the peel strength and the solder heat resistance, were carried out as in Example 1, except for using NISSO-PB B-3000, which had no functional group on the terminals, as the resin component. The results are shown in Table 2.

Comparative Example 4

[0082] Fabrication of a metal-clad laminate, and tests for measurements of the dielectric constant and dielectric loss tangent and for the peel strength and the solder heat resistance, were carried out as in Example 1, except for using the 1,4-polybutadiene synthesized in Production Example 3 as the resin component. The results are shown in Table 2.

TABLE-US-00002 TABLE 2 Comparative Comparative Comparative Comparative Example 1 Example 2 Example 1 Example 2 Example 3 Example 4 Copper foil peel 0.70 0.70 0.28 0.08 0.52 0.02 strength (N/mm.sup.2) Solder heat ○ ○ ○ ○ ○ x resistance Dielectric constant 2.56 2.41 2.53 2.32 2.25 2.42 Dielectric loss 0.030 0.015 0.029 0.027 0.014 0.026 tangent