EPOXY RESIN OLIGOMER

Abstract

An epoxy resin oligomer is provided. The epoxy resin oligomer is obtained by the reaction of at least a first reactant and a second reactant, and the molecular weight of the epoxy resin oligomer is between 3000 and 9000, wherein the mole ratio of the first reactant and the second reactant is between 1:0.9 and 0.9:1, and each of the first reactant and the second reactant is a compound having two polymerizable groups.

Claims

1. An epoxy resin oligomer obtained by a reaction of at least a first reactant and a second reactant, wherein a molecular weight of the epoxy resin oligomer is between 3000 and 9000, a mole ratio of the first reactant and the second reactant is between 1:0.9 and 0.9:1, and each of the first reactant and the second reactant is a compound having two polymerizable groups.

2. The epoxy resin oligomer of claim 1, wherein the epoxy resin oligomer is a solid at room temperature.

3. The epoxy resin oligomer of claim 1, wherein the first reactant is a bifunctional epoxy resin, and the second reactant is an amine compound containing dual active hydrogen.

4. The epoxy resin oligomer of claim 3, wherein the first reactant is selected from at least one of compounds represented by formula (1) to formula (4) below: ##STR00005## wherein X.sub.1 is a C4 to C18 alkyl group; X.sub.2 to X.sub.21 are each independently a hydrogen atom, a phosphorus atom, a C1 to C18 alkyl group, or halogen; Y is a sulfur atom, an oxygen atom, or a carbon atom; and n is 0 to 20.

5. The epoxy resin oligomer of claim 3, wherein an epoxy equivalent of the first reactant is between 150 g/mol and 1000 g/mol.

6. The epoxy resin oligomer of claim 3, wherein the second reactant is selected from at least one of compounds represented by formula (5) to formula (7) below: ##STR00006## wherein R.sub.a is a C1 to C20 alkyl group, a C5 to C12 cycloalkyl group, a C6 to C18 aryl group, or a C6 to C20 aralkyl group; R.sub.b is a C1 to C20 alkyl group or a C6 to C12 aryl group; and R.sub.c is a C1 to C20 alkyl group.

7. The epoxy resin oligomer of claim 3, wherein the epoxy resin oligomer is obtained by a reaction of at least the first reactant, the second reactant, and an additive, wherein based on a total weight of the first reactant, the second reactant, and the additive, a usage amount of the additive is greater than 0 wt % and equal to or less than 5 wt %.

8. The epoxy resin oligomer of claim 7, wherein the additive comprises a UV-resistant agent, an anti-yellowing agent, a flame retardant, a toughener, a plasticizer, or an abbrasion-resistant additive.

9. The epoxy resin oligomer of claim 1, wherein the epoxy resin oligomer is obtained by a reaction of at least the first reactant, the second reactant, and a catalyst, wherein the first reactant is a bifunctional epoxy resin, the second reactant is a bisphenol type compound, and based on a total weight of the first reactant, the second reactant, and the catalyst, a usage amount of the catalyst is 0.01 wt % to 3 wt %.

10. The epoxy resin oligomer of claim 9, wherein the first reactant is selected from at least one of compounds represented by foiiiiula (1) to formula (4) below: ##STR00007## wherein X.sub.1 is a C4 to C18 alkyl group; X.sub.2 to X.sub.21 are each independently a hydrogen atom, a phosphorus atom, a C1 to C18 alkyl group, or halogen; Y is a sulfur atom, an oxygen atom, or a carbon atom; and n is 0 to 20.

11. The epoxy resin oligomer of claim 9, wherein an epoxy equivalent of the first reactant is between 150 g/mol and 1000 g/mol.

12. The epoxy resin oligomer of claim 9, wherein the second reactant is selected from at least one of compounds represented by foiiiiula (8) to formula (9) below: ##STR00008## wherein W is a C1 to C20 alkyl group, a C5 to C12 cycloalkyl group, or a fluorene group, and X is a C1 to C20 alkyl group, a hydrogen atom, or halogen.

13. The epoxy resin oligomer of claim 9, wherein the catalyst comprises a Lewis base or an organic base.

14. The epoxy resin oligomer of claim 9, wherein the epoxy resin oligomer is obtained by a reaction of at least the first reactant, the second reactant, the catalyst, and an additive, wherein based on a total weight of the first reactant, the second reactant, the catalyst, and the additive, a usage amount of the additive is greater than 0 wt % and equal to or less than 5 wt %.

15. The epoxy resin oligomer of claim 14, wherein the additive comprises a UV-resistant agent, an anti-yellowing agent, a flame retardant, a toughener, a plasticizer, or an abbrasion-resistant additive.

Description

EXAMPLE 1

Preparation of Epoxy Resin Oligomer

[0045] At room temperature, 50 g (0.135 mole) of BE-188 epoxy resin (made by Changchun Chemical Company) and 13.2 g (0.150 mole) of cyclohexylamine were added in a 100 ml round-bottomed reaction flask. Then, at room temperature, the mixture was sufficiently stirred and mixed to react for 6 hours to obtain the epoxy resin oligomer of example 1 in the form of brittle solid, wherein the molecular weight was 5000±500.

Preparation of Composite Material

[0046] First, 20 g of the epoxy resin oligomer of example 1 was crushed into powder using a grinder (product name: RT-04A, made by Rong Tsong Precision Technology Co.). Then, a carbon fiber (model: 3K woven; made by Tairyfil, Formosa Plastic Group; fiber areal weight (FAW): 200 g/m.sup.2) having length and width dimensions of 30 cm×30 cm was taken and preheated on a 160° C. heating plate for 5 minutes. Then, the resulting powder was uniformly coated on the carbon fiber, and the temperature was maintained for 10 minutes, wherein the powder was melted within 1 second to 5 seconds and impregnated into the carbon fiber. Then, the temperature was lowered to room temperature to obtain the composite material of example 1, wherein the molecular weight of the polymer was within 40000 to 60000.

EXAMPLE 2

Preparation of Epoxy Resin Oligomer

[0047] At room temperature, 50 g (0.135 mole) of BE-188 epoxy resin (made by Changchun Chemical Company) and 16.2 g (0.134 mole) of 3,4-dimethylaniline were added in a 100 ml round-bottomed reaction flask. Then, the mixture was sufficiently stirred and mixed to perform a reaction for 24 hours to obtain the epoxy resin oligomer of example 2 in the form of brittle solid, wherein the molecular weight was 5000±500.

Preparation of Composite Material

[0048] First, 20 g of the epoxy resin oligomer of example 2 was crushed into powder using a grinder (product name: RT-04A, made by Rong Tsong Precision Technology Co.). Then, a carbon fiber (model: 3K woven; made by Tairyfil, Foil iosa Plastic Group; FAW: 200 g/m.sup.2) having length and width dimensions of 30 cm×30 cm was taken and preheated on a 160° C. heating plate for 5 minutes. Then, the resulting powder was uniformly coated on the carbon fiber, and the temperature was maintained for 1 hour, wherein the powder was melted within 1 second to 5 seconds and impregnated into the carbon fiber. Then, the temperature was lowered to room temperature to obtain the composite material of example 2, wherein the molecular weight of the polymer was within 70000 to 100000.

EXAMPLE 3

Preparation of Epoxy Resin Oligomer

[0049] At room temperature, 50 g (0.135 mole) of BE-188 epoxy resin (made by Changchun Chemical Company) and 30.5 g (0.134 mole) of bisphenol A were added in a 100 ml round-bottomed reaction flask. Then, the temperature was increased to 120° C., and stirring was continuously performed for half an hour until the bisphenol A was completely dissolved. Then, the resulting mixture was cooled to 60° C., then 0.1 g tetramethylammonium hydroxide was added, and then stirring was continuously performed for half an hour. Then, the temperature was lowered to room temperature, and after the mixture was left to stand for 24 hours, the epoxy resin oligomer of example 3 was obtained, wherein the molecular weight was 8000±500.

Preparation of Composite Material

[0050] First, 20 g of the epoxy resin oligomer of example 3 was crushed into powder using a grinder (product name: RT-04A, made by Rong Tsong Precision Technology Co.). Then, a carbon fiber (model: 3K woven; made by Tairyfil, Foil iosa Plastic Group; FAW: 200 g/m.sup.2) having length and width dimensions of 30 cm×30 cm was taken and preheated on a 160° C. heating plate for 5 minutes. Then, the resulting powder was uniformly coated on the carbon fiber, and the temperature was maintained for 1 hour, wherein the powder was melted within 2 seconds to 10 seconds and impregnated into the carbon fiber. Then, the temperature was lowered to room temperature to obtain the composite material of example 3, wherein the molecular weight of the polymer was within 40000 to 60000.

EXAMPLE 4

Preparation of Composite Material

[0051] First, 14.73 g of the epoxy resin oligomer of example 1 was crushed into powder using a grinder (product name: RT-04A, made by Rong Tsong Precision Technology Co.). Then, a uniaxial carbon fiber (model: Tairyfil TC-35R; made by Tairyfil, Formosa Plastic Group; FAW=200 g/m.sup.2) having length and width dimensions of 30 cm×30 cm was taken and preheated on a 160° C. heating plate for 5 minutes. Then, the resulting powder was unifoiiiily coated on the carbon fiber, and the temperature was maintained for 5 minutes, wherein the powder was melted within 1 second to 5 seconds and impregnated into the carbon fiber. Then, the temperature was lowered to room temperature to obtain the composite material of example 4, wherein the resin content (RC) of the composite material was 45% and the molecular weight of the polymer was within 40000 to 60000.

Comparative Example 1

Preparation of Composite Material

[0052] A thermosetting epoxy resin (model: 2552; made by SWancor Ind. Co., Ltd.) was impregnated in a uniaxial carbon fiber (model: Tairyfil TC-35R; made by Tairyfil, Foiiiiosa Plastic Group) having length and width dimensions of 30 cm×30 cm to obtain the composite material of comparative example 1, wherein the RC of the composite material was 45%.

[0053] Then, measurement of glass transition temperature was respectively performed on the composite materials of examples 1 to 4 and comparative example 1, measurements of 0° tensile strength, 0° tensile modulus, 0° flexural strength, 0° flexural modulus, and short beam shear strength were respectively performed on the composite materials of example 4 and comparative example 1, and measurements of 0° compressive strength and 0° compressive modulus were performed on the composite material of example 4. The above tests are as described below, and the test results are shown in Table 1.

Measurement of Glass Transition Temperature

[0054] First, the composite materials of examples 1 to 4 and comparative example 1 were respectively made into five test samples. Then, a differential scanning calorimeter (DSC) (made by TA Instruments, product name: DSC-Q20) was used to heat the test pieces from 20° C. to 150° C. under the conditions of a nitrogen gas atmosphere and a heating rate set to 10° C./min, and the temperature at which the loss tangent (tans) reached a maximum value was considered the glass transition temperature (° C.). In general, a greater numeric value of glass transition temperature means a better thermal stability.

Measurement of 0° Tensile Strength

[0055] First, the composite materials of example 4 and comparative example 1 were respectively made into five test pieces. Then, the 0° tensile strength of each of the five test pieces of example 4 and the five test pieces of comparative example 1 was measured according to the test specifications of ASTM D3039. In general, a greater numeric value of 0° tensile strength means a better mechanical strength.

Measurement of 0° Tensile Modulus

[0056] First, the composite materials of example 4 and comparative example 1 were respectively made into five test pieces. Then, the 0° tensile modulus of each of the five test pieces of example 4 and the five test pieces of comparative example 1 was measured according to the test specifications of ASTM D3039. In general, a greater numeric value of 0° tensile modulus means a better mechanical strength.

Measurement of 0° Flexural Strength

[0057] First, the composite materials of example 4 and comparative example 1 were respectively made into five test pieces. Then, the 0° flexural strength of each of the five test pieces of example 4 and the five test pieces of comparative example 1 was measured according to the test specifications of ASTM D790. In general, a greater numeric value of 0° flexural strength means a better mechanical strength.

Measurement of 0° Flexural Modulus

[0058] First, the composite materials of example 4 and comparative example 1 were respectively made into five test pieces. Then, the 0° flexural modulus of each of the five test pieces of example 4 and the five test pieces of comparative example 1 was measured according to the test specifications of ASTM D790. In general, a greater numeric value of 0° flexural modulus means a better mechanical strength.

Measurement of 0° Compressive Strength

[0059] First, the composite material of example 4 was made into five test pieces. Then, the 0° compressive strength of each of the five test pieces of example 4 was measured according to the test specifications of ASTM D3410. In general, a greater numeric value of 0° compressive strength means a better mechanical strength.

Measurement of 0° Compressive Modulus

[0060] First, the composite material of example 4 was made into five test pieces. Then, the 0° compressive modulus of each of the five test pieces of example 4 was measured according to the test specifications of ASTM D3410. In general, a greater numeric value of 0° compressive modulus means a better mechanical strength.

Measurement of Short Beam Shear Strength

[0061] First, the composite materials of example 4 and comparative example 1 were respectively made into five test pieces. Then, the short beam shear strength of each of the five test pieces of example 4 and the five test pieces of comparative example 1 was measured according to the test specifications of ASTM D2344. In general, a greater numeric value of short beam shear strength means a better mechanical strength.

TABLE-US-00001 TABLE 1 Exam- Exam- Exam- Exam- Comparative ple 1 ple 2 ple 3 ple 4 example 1 0° tensile — — — 1700 ± 80  2200 ± 100 strength (MPa) 0° tensile — — — 113 ± 5 125 ± 5 modulus (GPa) 0° flexural — — — 1032 ± 45 1100 ± 50 strength (MPa) 0° flexural — — — 100 ± 5 125 ± 5 modulus (GPa) 0° compressive — — —  645 ± 60 — strength (MPa) 0° compressive — — — 122 ± 5 — modulus (GPa) Short beam shear — — —  55 ± 3  85 ± 5 strength (MPa) Glass transition 87 ± 1 98 ± 1 94 ± 2  87 ± 1 130 ± 2 temperature (° C.)

[0062] It can be known from Table 1 that, the 0° tensile strength of the composite material of example 4 was about 77% of the 0° tensile strength of the composite material of comparative example 1; the 0° tensile modulus of the composite material of example 4 was about 90% of the 0° tensile modulus of the composite material of comparative example 1; the 0° flexural strength of the composite material of example 4 was about 94% of the 0° flexural strength of the composite material of comparative example 1; the 0° flexural modulus of the composite material of example 4 was about 80% of the 0° flexural modulus of the composite material of comparative example 1; and the short beam shear strength of the composite material of example 4 was about 65% of the short beam shear strength of the composite material of comparative example 1. The results show that, during the preparation of the composite materials via in-situ polymerization, the epoxy resin oligomer of example 4 can achieve good impregnation effect at a lower impregnation temperature.

[0063] Moreover, although measurements of 0° tensile strength, 0° tensile modulus, 0° flexural strength, 0° flexural modulus, 0° compressive strength, 0° compressive modulus, and short beam shear strength were not performed on the composite materials of examples 1 to 3, according to the measurement results of the composite materials of example 4 and comparative example 1, those having ordinary skill in the art should understand that the epoxy resin oligomers of examples 1 to 3 can also achieve good impregnation effect at a lower impregnation temperature, and therefore the composite materials of examples 1 to 3 also have good mechanical strength.

[0064] Although the invention has been described with reference to the above embodiments, it will be apparent to one of ordinary skill in the art that modifications to the described embodiments may be made without departing from the spirit of the invention. Accordingly, the scope of the invention is defined by the attached claims not by the above detailed descriptions.