THERMOPLASTIC POLYMER-BASED COMPOSITE MATERIAL AND PREPARATION METHOD THEREOF

Abstract

A thermoplastic polymer-based composite material and a preparation method thereof are provided. The thermoplastic polymer-based composite material is obtained by impregnating a reinforcing material with a mixture or an oligomer of an epoxy resin, a bisphenol A/F, and a catalyst and then performing an in-situ polymerization. The thermoplastic polymer-based composite material is less expensive to produce, has an optimal impregnation effect, excellent secondary processing performance, high heat resistance, desirable mechanical properties and excellent overall performance.

Claims

1. A thermoplastic polymer-based composite material obtained by an in-situ polymerization reaction after impregnating a reinforcing material with a mixture or an oligomer of an epoxy resin, a bisphenol A/F, and a catalyst, wherein a number of the bisphenol A/F in mole is 0.3-0.6 time a number of epoxy functional groups of the epoxy resin in mole, and a weight percentage of the catalyst in the mixture or the oligomer is 0.1%-5%.

2. The thermoplastic polymer-based composite material according to claim 1, wherein the epoxy resin has the following general structural formula: ##STR00002## wherein, R is a C.sub.2-C.sub.18 alkyl, an aryl, a cycloalkyl group, a bisphenol A structure, a bisphenol F structure, a bisphenol S structure, a halogenated bisphenol A structure, a halogenated bisphenol F structure, a halogenated bisphenol S structure, a hydrogenated bisphenol A structure, a hydrogenated bisphenol F structure, or a hydrogenated bisphenol S structure; and n is 0-20.

3. The thermoplastic polymer-based composite material according to claim 1, wherein the catalyst is at least one selected from the group consisting of a quaternary ammonium salt, a tertiary phosphine, and a quaternary phosphonium salt.

4. The thermoplastic polymer-based composite material according to claim 1, wherein the reinforcing material is at least one selected from the group consisting of glass fiber, carbon fiber, aramid fiber, Kevlar fiber, basalt fiber, poly (p-phenylenebenzobisoxazole) (PBO) fiber, nylon fiber, ultra-high molecular weight polyethylene (UHMWPE) fiber, polyimide fiber, and polyester fiber.

5. The thermoplastic polymer-based composite material according to claim 1, wherein a predetermined amount of the epoxy resin is added to form a branched polymer or a lightly crosslinked polymer, and the predetermined amount is determined for controlling a cross-linking density without reaching a gel point and controlling the branched polymer or the lightly crosslinked polymer to be a soluble, fusible thermoplastic polymer.

6. A method for preparing the thermoplastic polymer-based composite material according to claim 1, comprising the following steps: (1) firstly heating a part of the epoxy resin to 80° C-150° C., then adding the bisphenol A/F to dissolve the part of the epoxy resin to obtain a mixed solution, and stirring the mixed solution evenly to obtain a first component for subsequent use; (2) dispersing the catalyst into the remaining of the epoxy resin to obtain a second component for subsequent use; and (3) mixing the first component and the second component to obtain the mixture, then impregnating the reinforcing material in the mixture; and after the impregnating is completed to obtain an impregnated reinforcing material, performing the in-situ polymerization on the impregnated reinforcing material to obtain the thermoplastic polymer-based composite material.

7. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein in step (3), a volume ratio of the first component to the second component ranges from 10:1 to 1:1.

8. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein in step (3), the impregnating is performed at a temperature of 80° C-120° C.

9. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein in step (3), the in-situ polymerization is performed at a temperature of 80° C-200° C.

10. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein the epoxy resin has the following general structural formula: ##STR00003## wherein, R is a C.sub.2-C.sub.18 alkyl, an aryl, a cycloalkyl group, a bisphenol A structure, a bisphenol F structure, a bisphenol S structure, a halogenated bisphenol A structure, a halogenated bisphenol F structure, a halogenated bisphenol S structure, a hydrogenated bisphenol A structure, a hydrogenated bisphenol F structure, or a hydrogenated bisphenol S structure; and n is 0-20.

11. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein the catalyst is at least one selected from the group consisting of a quaternary ammonium salt, a tertiary phosphine, and a quaternary phosphonium salt.

12. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein the reinforcing material is at least one selected from the group consisting of glass fiber, carbon fiber, aramid fiber, Kevlar fiber, basalt fiber, poly (p-phenylenebenzobisoxazole) (PBO) fiber, nylon fiber, ultra-high molecular weight polyethylene (UHMWPE) fiber, polyimide fiber, and polyester fiber.

13. The method for preparing the thermoplastic polymer-based composite material according to claim 6, wherein a predetermined amount of the epoxy resin is added to form a branched polymer or a lightly crosslinked polymer, and the predetermined amount is determined for controlling a cross-linking density without reaching a gel point and controlling the branched polymer or the lightly crosslinked polymer to be a soluble, fusible thermoplastic polymer.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] To better understand the present invention, the content of the present invention is further illustrated below with reference to the embodiments, understanding that these are only exemplary embodiments of the invention and, therefore, are not to be considered to be limiting of the scope of the invention.

Embodiment 1

[0029] 1. Preparation of component A

[0030] 100 g of bisphenol A epoxy resin (850S, EEW=185-195, purchased from Nantong Xingchen Synthetic Materials Co., Ltd.) is weighed and is heated to 115° C. Then, 80 g of bisphenol A is added, and stirred evenly until the bisphenol A is completely dissolved. The mixture produced is the component A.

[0031] The viscosity of the component A at 110° C. is determined to be 150 mPa s

[0032] After the component A is kept at 110° C. for 3 days, the viscosity of the component A at 110° C. is determined to be 380 mPa s

2. Preparation of component B

[0033] 100 g of bisphenol A epoxy resin (850S, EEW=185-195, purchased from Nantong Xingchen Synthetic Materials Co., Ltd.) is weighed and 4 g methyl triphenyl phosphonium bromide is added to disperse evenly. The obtained mixture is the component B.

[0034] The viscosity of the component B at 80° C. is determined to be 220 mPa s

[0035] After the component B is kept at 80° C. for 8 days, the viscosity of the component B at 80° C. is determined to be 420 mPa s

3. Mixing of component A and component B

[0036] The components A and B are mixed evenly at a volume ratio of 5:1 to obtain a mixture, and the viscosity of the mixture at 80° C. is determined to be 408 mPa s After performing heat preservation at 80° C. for 1 hour, the viscosity of the mixture at 80° C. is determined to be 1964 mPa s. The heat preservation is continued for 3 hours, and then the temperature is increased to 160° C. and kept for 1 hour. The glass transition temperature (Tg) of the product is determined to be 113° C.

4. Preparation of thermoplastic polymer-based composite material

[0037] Nine pieces of 15 cm×15 cm glass fiber cloth are cut and spread on the glass plate. The components A and B are mixed at a volume ratio of 5:1 to obtain a mixture and kept the temperature at 80° C. The mixture is evenly coated on the glass fiber cloth with a brush and impregnates the glass fiber cloth. The impregnated glass fiber cloth is placed in an oven at 120° C. for 2 hours to perform in-situ polymerization to obtain 9 pieces of composite prepreg sheets.

[0038] The 9 pieces of composite prepreg sheets are stacked together and put into a mold of a hot press. The mold temperature is 160° C. After hot pressing for 5 minutes, the composite prepreg sheets are taken out, and then cooled to obtain a thermoplastic composite laminate.

[0039] It can be seen from Embodiment 1 that at a certain temperature, bisphenol A can be fully dissolved in the epoxy resin to form a low-viscosity solution, and the low-viscosity solution has a long storage period at a higher temperature. After the catalyst is dispersed in the epoxy resin, it can have a long storage period at higher temperatures. After mixing of the components A and B, they can react quickly to form a polymer. The present invention provides a low viscosity intermediary solution with optimal physical properties for effectively impregnating the reinforced material to then yield a thermoplastic polymer-based composite material. The result is obtained without the shortcomings of the prior methods set forth in preceding paragraphs.

Embodiment 2

[0040] Conditions are consistent with Embodiment 1 except that the catalyst is changed to be benzyltrimethylammonium chloride, and a thermoplastic composite material laminate similar to that of Embodiment 1 is obtained.

Embodiment 3

[0041] Conditions are consistent with Embodiment 1 except that the catalyst is changed to be triphenylphosphine, and a thermoplastic composite material laminate similar to that of Embodiment 1 is obtained.

[0042] It can be seen from Embodiments 2 and 3 that by using different catalysts, thermoplastic composite materials similar to that of Embodiment 1 can be obtained.

Embodiment 4

[0043] Conditions are consistent with Embodiment 1 except that the bisphenol A epoxy resin is changed to be a bisphenol F epoxy resin (EEW=165-175, purchased from Nantong Xingchen Synthetic Material Co., Ltd.), and the bisphenol A is changed to be a bisphenol F. A thermoplastic composite laminate can also be successfully prepared, but the heat resistance is slightly low with the Tg of 76° C.

[0044] It can be seen from Embodiment 4 that by using the bisphenol F and the bisphenol F epoxy resin, a thermoplastic composite material similar to that of Embodiment 1 can also be obtained.

Embodiment 5

[0045] Conditions are consistent with Embodiment 1 except that 10% of the bisphenol A epoxy resin is changed to be a phenolic epoxy resin (NPPN-631, EEW=168-178, purchased from Nanya Epoxy Resin (Kunshan) Co., Ltd.). A thermoplastic composite material laminate can also be successfully prepared. The Tg of the product is determined to be 122° C.

[0046] The obtained composite material laminate is placed in an oven at 350° C. for half an hour, and it is found that the polymer matrix can be melted.

[0047] It can be seen from Embodiment 4 that the composite material obtained by adding a small amount of a multifunctional epoxy resin also has thermoplastic property and the heat resistance is improved.