Phosphazene compound, a prepreg and a composite metal laminate

Abstract

The present invention relates to a phosphazene compound and a prepreg and a composite metal laminate. The phosphazene compound has a structure as shown in Formula (I). The present invention obtains a phosphazene compound using an M group having specific components. The composite metal laminates prepared by the epoxy resin composition comprising the phosphazene compound have low dielectric properties, good heat resistance and mechanical properties and is a low dielectric material also having great economic properties and being environmental friendly.

Claims

1. A phosphazene compound, comprising a molecular structure as shown in Formula I: ##STR00027## in Formula I, R.sub.1 is substituted or unsubstituted aromatic hydrocarbon group or substituted or unsubstituted aliphatic hydrocarbon group; R.sub.2, R.sub.3, R.sub.6 and R.sub.7 are independently any organic group satisfying the chemical environment thereof; R.sub.4 and R.sub.5 are independently any inert nucleophilic group; M is any one of cyclotriphosphazene groups M.sub.1, cyclic ring consisting of four or more phosphazene groups M.sub.2, or non-cyclic polyphosphazene groups M.sub.3, or a combination of at least two of them; n is an integer greater than or equal to 1 and m is an integer greater than or equal to zero; each a and b is an integer greater than or equal to zero, and a+b+2 equals to two times of the number of phosphorus atoms in M group.

2. The phosphazene compound of claim 1, wherein R.sub.1 is any one of substituted or unsubstituted straight-chain alkylene, substituted or unsubstituted branched alkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, substituted or unsubstituted arylenealkylene, substituted or unsubstituted alkylenearylene, substituted or unsubstituted cycloalkylenearylene, substituted or unsubstituted heteroarylenealkylene or substituted or unsubstituted alkyleneheteroarylene.

3. The phosphazene compound of claim 1, wherein R.sub.2 and R.sub.7 are independently any one of substituted or unsubstituted straight-chain alkylene, substituted or unsubstituted branched alkylene, substituted or unsubstituted cycloalkylene, substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, substituted or unsubstituted arylenealkylene, substituted or unsubstituted alkylenearylene, substituted or unsubstituted cycloalkylenearylene, substituted or unsubstituted heteroarylenealkylene, or substituted or unsubstituted alkyleneheteroarylene.

4. The phosphazene compound of claim 1, wherein R.sub.3 and R.sub.6 are independently any one of substituted or unsubstituted straight-chain or branched alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted aralkyl, substituted or unsubstituted heteroarylalkyl.

5. The phosphazene compound of claim 1, wherein R.sub.4 and R.sub.5 are independently any one of substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted arylalkoxy, substituted or unsubstituted alkylaryloxy, substituted or unsubstituted heteroarylalkoxy, substituted or unsubstituted alkylheteroaryloxy, substituted or unsubstituted carboxylate group, substituted or unsubstituted carbonate group, substituted or unsubstituted sulfonate group, substituted or unsubstituted phosphonate group, or a combination of at least two of them.

6. The phosphazene compound of claim 1, wherein M.sub.1 has a structure of ##STR00028## M.sub.2 has a structure of ##STR00029## wherein x is greater than or equal to 4; M.sub.3 has a structure of ##STR00030## wherein y is greater than or equal to 3.

7. A method for preparing the phosphazene compound of claim 1, obtaining the phosphazene compound by carrying out a nucleophilic substitution reaction of phosphazene chloride and nucleophile.

8. A prepreg prepared by impregnating a substrate with an epoxy resin composition comprising the phosphazene compound of claim 1 or coating an epoxy resin composition comprising the phosphazene compound of claim 1 onto a substrate.

9. The prepreg of claim 8, wherein the substrate is a glass fiber substrate, a polyester substrate, a polyimide substrate, a ceramic substrate or a carbon fiber substrate.

Description

EMBODIMENTS

(1) The technical solutions of the present invention are further explained by combining with the following examples.

(2) In the following examples, the used raw material of phosphazene chloride (for example hexachlorocyclotriphosphazene) can be obtained by the synthetic methods described in the present invention or known in the art. The other raw materials can be obtained through commercial purchase.

Example 1

(3) The phosphazene compound of the present example has the following structure:

(4) ##STR00015##
and the preparation method thereof is shown as follows.

(5) 1 mol of hexachlorocyclotriphosphazene, 200 ml of acetone, 4 mol of sodium methylate, 1 mol of ethylene glycol were added to a 3-neck glass reactor having a volume of 2000 ml and having a stirring apparatus. While stirring, nitrogen was fed therein, and the reactor was heated to 60 C. 620 g of 20% sodium hydroxide solution was dripped within 60 min, and then the mixture was held at 60 C., stirred and reacted for 8 hours. After reaction, the inorganic constituents and water in the system were removed by physical method. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of butanedioic acid was added therein, and the mixture was stirred and reacted for 5 hours, followed by adding 1 mol of ethanol and continuing to stir and make the mixture react for 2 hours. After reaction, the impurities and water in the system were removed by physical methods; and the solvent in the system was distilled off to obtain 1 mol of ester compound A having an ester equivalent of 180 g/eq and a structure as shown above.

(6) The obtained compound A was characterized by nuclear magnetic resonance hydrogen spectrum, and the results are as follows:

(7) .sup.1H NMR (CDCl.sub.3, 500 MHz): 4.15-4.22 (m, 4H, COOCH.sub.2), 3.83 (m, 2H, COOCH.sub.2CH.sub.2O), 3.42 (s, 12H, OCH.sub.3), 2.58-2.60 (m, 4H, COCH.sub.2CH.sub.2CO), 2.1 (m, 3H, COCH.sub.3), 1.63 (m, 2H, CH.sub.3CH.sub.2O), 1.0 (m, 3H, CH.sub.3CH.sub.2O).

(8) Characteristic peak positions in infrared spectroscopy: ester carbonyl, 1730-1740 cm.sup.1; COC in ester group, 1200 cm.sup.1; characteristic absorption peak of PN bond in the skeleton of phosphazene, 1217 cm.sup.1; PN in the skeleton of phosphazene, 874 cm.sup.1; absorption peak of methyl ether, 2995.3 cm.sup.1; absorption peak of POC bond, 1035 cm.sup.1; absorption peak of CH.sub.2O, 2983 cm.sup.1.

(9) 90 g of the above ester compound A as a curing agent was added into 100 g of o-cresol novolac epoxy resin with an epoxide equivalent of 200 g/eq and 0.2 g of curing accelerator 2-methylimidazole to prepare an epoxy resin composition. A standard copper clad laminate sample meeting the national, UL and other standards was prepared by using this epoxy resin composition according to generally used copper clad laminate production process. The copper clad laminate is named as copper clad laminate a and the properties thereof are measured and the results are shown in Table 1.

Example 2

(10) The phosphazene compound of the present example has the following structure:

(11) ##STR00016##
and the preparation method thereof is shown as follows.

(12) 1 mol of hydroquinone, 1 mol of benzoic acid, 200 ml of acetone were added to a 3-neck glass reactor having a volume of 2000 ml and having a stirring apparatus. 3 mL of 98% concentrated sulfuric acid was dripped therein and the mixture conducted esterification reaction for 1 h, followed by adding 1 mol of hexachlorocyclotriphosphazene and 4 mol of phenol and stirring. While stirring, nitrogen was fed therein, and the reactor was heated to 60 C. 621 g of 20% sodium hydroxide solution was dripped within 60 min, and then the mixture was held at 60 C., stirred and reacted for 10 hours. After reaction, the inorganic constituents and water in the system were removed by physical method. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of terephthalic acid was added therein, and the mixture was continued to react for 3 hours, followed by adding 1 mol of hexachlorocyclotriphosphazene and continuing to react for 5 hours, and then adding 4 mol of phenol and 1 mol of hydroquinone and continuing to react for 8 hours. After reaction, the impurities and water in the system were removed by physical methods; and the solvent in the system was distilled off to obtain 1 mol of ester compound B having an ester equivalent of 410 g/eq and a structure as shown above.

(13) The obtained compound B was characterized by nuclear magnetic resonance hydrogen spectrum, and the results are as follows:

(14) .sup.1H NMR (CDCl.sub.3, 500 MHz): 8.28-8.32 (m, 4H,

(15) ##STR00017##
7.4-8.1 (m, 10H,

(16) ##STR00018##
6.8-7.0 (S, 48H, hydrogen in

(17) ##STR00019##

(18) Characteristic peak positions in infrared spectroscopy: ester carbonyl, 1730-1740 cm.sup.1; COC in ester group, 1200 cm.sup.1; characteristic absorption peak of PN bond in the skeleton of phosphazene, 1217 cm.sup.1; PN in the skeleton of phosphazene, 874 cm.sup.1; absorption peak of POC bond, 1035 cm.sup.1; para-position substituted benzene ring, 860-790 cm.sup.1.

(19) 205 g of the above ester compound B as a curing agent was added into 100 g of o-cresol novolac epoxy resin with an epoxide equivalent of 200 g/eq and 0.2 g of curing accelerator 2MI to prepare an epoxy resin composition. A standard copper clad laminate sample meeting the national, UL and other standards was prepared by using this epoxy resin composition according to generally used copper clad laminate production process. The copper clad laminate is named as copper clad laminate b and the properties thereof are measured and the results are shown in Table 1.

Example 3

(20) The phosphazene compound of the present example has the following structure:

(21) ##STR00020##
and the preparation method thereof is shown as follows.

(22) 1 mol of ethylene glycol, 1 mol of acetic acid, 200 ml of acetone were added to a 3-neck glass reactor having a volume of 2000 ml and having a stirring apparatus. 3 mL of 98% concentrated sulfuric acid was dripped therein and the mixture conducted esterification reaction for 1 h, followed by adding 1 mol of hexachlorocyclotriphosphazene and 4 mol of sodium methylate and stirring. While stirring, nitrogen was fed therein, and the reactor was heated to 60 C. 620 g of 20% sodium hydroxide solution was dripped within 60 min, and then the mixture was held at 60 C., stirred and reacted for 15 hours. After reaction, the inorganic constituents and water in the system were removed by physical methods. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of terephthalic acid was added therein, and the mixture was continued to be held at 60 C. and react for 3 hours, followed by adding 1 mol of hexachlorocyclotriphosphazene and continuing to react for 3 hours, and then adding 4 mol of sodium methylate and continuing to react for 5 hours, and then dripping 1 mol of hydroquinone and continuing to react for 4 hours. After reaction, the inorganic constituents and water in the system were removed by physical methods. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of acetic acid was added therein, and the mixture reacted for 3 hours. After reaction, the impurities and water in the system were removed by physical methods; and the solvent in the system was distilled off to obtain 1 mol of ester compound C having an ester equivalent of 225 g/eq and a structure as shown above.

(23) The obtained compound C was characterized by nuclear magnetic resonance hydrogen spectrum, and the results are as follows:

(24) .sup.1H NMR (CDCl.sub.3, 500 MHz): 8.28-8.32 (m, 4H,

(25) ##STR00021##
6.7-6.9 (m, 4H,

(26) ##STR00022##
4.32 (m, 2H, COOCH.sub.2CH.sub.2O), 3.83 (m, 2H, COOCH.sub.2CH.sub.2O), 3.42 (s, 24H, OCH.sub.3), 2.1 (m, 6H, COCH.sub.3).

(27) Characteristic peak positions in infrared spectroscopy: ester carbonyl, 1730-1740 cm.sup.1; COC in ester group, 1200 cm.sup.1; characteristic absorption peak of PN bond in the skeleton of phosphazene, 1217 cm.sup.1; PN in the skeleton of phosphazene, 874 cm.sup.1; absorption peak of methyl ether, 2995.3 cm.sup.1; absorption peak of POC bond, 1035 cm.sup.1; absorption peak of CH.sub.2O, 2983 cm.sup.1; para-position substituted benzene ring, 860-790 cm.sup.1.

(28) 128 g of the above ester compound C as a curing agent was added into 100 g of o-cresol novolac epoxy resin with an epoxide equivalent of 1200 g/eq and 0.2 g of curing accelerator 2MI to prepare an epoxy resin composition. A standard copper clad laminate sample meeting the national, UL and other standards was prepared by using this epoxy resin composition according to generally used copper clad laminate production process. The copper clad laminate is named as copper clad laminate c and the properties thereof are measured and the results are shown in Table 1.

Example 4

(29) The phosphazene compound of the present example has the following structure:

(30) ##STR00023##
and the preparation method thereof is shown as follows.

(31) 1 mol of hydroquinone, 1 mol of acetic acid, 200 ml of acetone were added to a 3-neck glass reactor having a volume of 2000 ml and having a stirring apparatus. 3 mL of 98% concentrated sulfuric acid was dripped therein and the mixture conducted esterification reaction for 1 h, followed by adding 1 mol of hexachlorocyclotriphosphazene and 4 mol of sodium methylate and stirring. While stirring, nitrogen was fed therein, and the reactor was heated to 60 C. 621 g of 20% sodium hydroxide solution was dripped within 60 min, and then the mixture was held at 60 C., stirred and reacted for 10 hours. After reaction, the inorganic constituents and water in the system were removed by physical methods. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of terephthalic acid was added therein, and the mixture was continued to be held at 60 C. and react for 3 hours, followed by adding 1 mol of hexachlorocyclotriphosphazene and continuing to react for 5 hours, and then adding 4 mol of sodium methylate and 1 mol of hydroquinone and continuing to react for 8 hours. After reaction, the inorganic constituents and water in the system were removed by physical methods. Then 3 mL of 98% concentrated sulfuric acid was dripped and 1 mol of acetic acid was added therein, and the mixture reacted for 2 hours. After reaction, the impurities and water in the system were removed by physical methods; and the solvent in the system was distilled off to obtain 1 mol of ester compound D having an ester equivalent of 250 g/eq and a structure as shown above.

(32) The obtained compound D was characterized by nuclear magnetic resonance hydrogen spectrum, and the results are as follows:

(33) .sup.1H NMR (CDCl.sub.3, 500 MHz): 8.28-8.32 (m, 4H,

(34) ##STR00024##
6.7-6.9 (m, 8H,

(35) ##STR00025##
3.42 (s, 24H, OCH.sub.3), 2.1 (m, 6H, COCH.sub.3).

(36) Characteristic peak positions in infrared spectroscopy: ester carbonyl, 1730-1740 cm.sup.1; COC in ester group, 1200 cm.sup.1; characteristic absorption peak of PN bond in the skeleton of phosphazene, 1217 cm.sup.1; PN in the skeleton of phosphazene, 874 cm.sup.1; absorption peak of methyl ether, 2995.3 cm.sup.1; absorption peak of POC bond, 1035 cm.sup.1; absorption peak of CH.sub.2O, 2983 cm.sup.1; para-position substituted benzene ring, 860-790 cm.sup.1.

(37) 125 g of the above ester compound D as a curing agent was added into 100 g of o-cresol novolac epoxy resin with an epoxide equivalent of 200 g/eq and 0.2 g of curing accelerator 2MI to prepare an epoxy resin composition. A standard copper clad laminate sample meeting the national, UL and other standards was prepared by using this epoxy resin composition according to generally used copper clad laminate production process. The copper clad laminate is named as copper clad laminate d and the properties thereof are measured and the results are shown in Table 1.

Comparative Example 1

(38) 200 g of o-cresol novolac epoxy resin with an epoxide equivalent of 200 g/eq was added into 105 g of linear phenolic resin curing agent with a phenolic hydroxyl equivalent of 105 g/eq and 70 g of hexaphenoxyphosphazene which is used as flame retardant and 0.2 g of 2-methylimidazole, and the mixture was dissolved in a suitable amount of butanone to form a solution. A copper clad laminate e having a resin content of 50% was prepared by using standard glass fiber cloth according to a well-known method. The properties of the copper clad laminate e are shown in Table 1.

Comparative Example 2

(39) 200 g of o-cresol novolac epoxy resin with an epoxide equivalent of 200 g/eq was added into 220 g of a resin compound having a structure of Formula (I) and an ester equivalent of 220 g/eq and 70 g of hexaphenoxyphosphazene which is used as flame retardant and 0.2 g of pyridine, and the mixture was dissolved in a suitable amount of butanone to form a solution. A copper clad laminate f having a resin content of 50% was prepared by using standard glass fiber cloth according to a well-known method. The properties of the copper clad laminate f are shown in Table 1.

(40) ##STR00026##

(41) The test results of products of Examples and Comparative Examples are shown in Table 1 (the specific test methods are not described considering that they are well-known by those skilled in the art).

(42) TABLE-US-00001 TABLE 1 Copper Copper Copper Copper Copper Copper clad clad clad clad clad clad Test Item laminate a laminate b laminate c laminate d laminate e laminate f Tg (DSC) 183 180 175 178 150 135 ( C.) T-peeling 1.93 2.03 2.01 1.90 1.71 1.69 strength (kg/mm.sup.2) Interlaminar 1.64 1.65 1.75 1.73 0.80 0.82 peeling strength (kg/mm.sup.2) Saturated water 0.34 0.32 0.33 0.35 0.58 0.60 absorption (%) Dielectric 3.32 3.25 3.30 3.27 4.25 4.3 constant (1 GHz) Dielectric loss 0.0056 0.005 0.006 0.0058 0.13 0.14 (1 GHz)

(43) As can be seen from Table 1, the copper clad laminates of the present invention prepared by using an epoxy resin composition prepared by using a compound having a structure of Formula (I) as a curing agent have a dielectric constant (1 GHz) of 3.28-3.33, a dielectric loss (1 GHz) of 0.005-0.006, a Tg which can be 175 C. or greater, a T-peeling strength which can be 1.90 kg/mm.sup.2 or greater, an interlaminar peeling strength which can be 1.64 kg/mm.sup.2 or greater, and a saturated water absorption which can be 0.35% or less, which are much better than the properties of the copper clad laminates of Comparative Examples.

(44) The present invention illustrates the phosphazene compound, prepreg and composite metal laminate of the present invention by the above examples, but the present invention is not limited to the above examples; that is to say, it does not mean that the present invention must be conducted by relying on the above examples. Those skilled in the art should understand that any modification to the present invention, any equivalent replacement of each raw material of the products of the present invention and the addition of auxiliary ingredients, the selection of specific embodiment and the like all fall into the protection scope and the disclosure scope of the present invention.