阅读说明：本技术 丁羟推进剂玻璃化转变温度的测试方法 (The test method of HTPB propellant glass transition temperature ) 是由 廖建苹 王娜 谢世刚 闫志佳 黄水生 黄曦 胡芊悦 于 2019-08-28 设计创作，主要内容包括：本发明公开了一种丁羟推进剂玻璃化转变温度的测试方法,包括以下步骤：1)样品制备成型；2)选择动态热机械仪配备的压缩夹具；3)采用动态热机械仪压缩形变模式进行测试,设置动态参数,控制升温速率为2~2.5℃/min,应力应变频率1Hz,动态力为2.0~3.0N,静态力为0.1~0.5N,振幅10~30μm,样品测试前置于低于-120℃环境温度中恒温后,开始升温测试。该测试方法已在多种发动机玻璃化转变温度测试中进行了应用,玻璃化转变温度明显,灵敏度高。(The invention discloses a kind of test methods of HTPB propellant glass transition temperature, comprising the following steps: 1) sample preparation forms；2) compression clamp that selection dynamic thermomechanical instrument is equipped with；3) it is tested using dynamic thermomechanical instrument compressive deformation mode, dynamic parameter is set, control heating rate is 2 ~ 2.5 DEG C/min, ess-strain frequency 1Hz, dynamic force be 2.0 ~ 3.0N, static force be 0.1 ~ 0.5N, 10 ~ 30 μm of amplitude, it is positioned below before sample test in -120 DEG C of environment temperatures after constant temperature, starts to warm up test.The test method is applied in the test of various engines glass transition temperature, and glass transition temperature is obvious, high sensitivity.)

1. the test method of HTPB propellant glass transition temperature, which comprises the following steps:

1) sample preparation, using propellant sampling machine by propellant sample according to casting direction prepare slabbing, be then made with Dynamic thermomechanical analysis apparatus with the sample that is consistent of compression grip size；

2) sample is placed in compression clamp middle position, adjusts compression clip by the compression clamp that selection dynamic thermomechanical instrument is equipped with Have push rod, contacts compression clamp with propellant sample surfaces, it is ensured that compression clamp and sample are matched with temperature sensor and other Part is contactless, closes insulated hold；

3) it is tested using dynamic thermomechanical instrument compressive deformation mode, dynamic parameter is set, control heating rate is 2 ~ 2.5 DEG C/min, ess-strain frequency 1Hz, dynamic force is 2.0 ~ 3.0N, and static force is 0.1 ~ 0.5N, and 10 ~ 30 μm of amplitude, sample is surveyed It is positioned below before examination in -120 DEG C of environment temperatures after constant temperature, starts to warm up test；

HTPB propellant glass transition temperature is determined according to the glass transition temperature curve of test.

2. according to the method described in claim 1, it is characterized by: in step 1), sheet sample with a thickness of 2 ± 0.5mm.

3. according to the method described in claim 1, it is characterized by: in step 1), last sample obtained be diameter 10 ± 0.5mm cylindrical body, cylindrical body vertical sampling from sheet sample.

4. method according to claim 1 to 3, it is characterised in that: the sample that step 1) prepares is placed on dry 2h discharges stress in dry device.

5. according to the method described in claim 1, it is characterized by: the compression clamp in step 2 passes through dynamic matter using preceding Amount, empty set system, system stiffness and temperature correction.

6. according to the method described in claim 1, it is characterized by: control heating rate is 2.5 DEG C/min, ess-strain frequency 1Hz, dynamic force 2.5N, static force 0.5N.

7. according to the method described in claim 1, it is characterized by: constant temperature time is 10min or more in step 3), using liquid nitrogen Cooling reaches required environment temperature.

Technical field

The invention belongs to propellant technical fields, are related to the test method of HTPB propellant glass transition temperature, specifically For the method for testing HTPB propellant glass transition temperature using dynamic thermomechanical instrument compressive deformation mode.

Background technique

Composite solidpropellant is the composite material containing energy with particular characteristic using macromolecule as matrix, studies macromolecule System is exactly to study its viscoplasticity, and glass transition temperature is one of the parameter for reacting the performance of propellant.

Currently used propellant glass transition temperature test is all made of thermomechanical analysis (TMA), plavini, heat differential Show scanning calorimetry (DSC), TMA method applies certain pressure intensity to sample using measuring probe, varies with temperature, and sample generates certain Deformation, testing its deformation inflection point is glass transition temperature；Plavini is using the coefficient of expansion of dilatometer measurement sample with temperature The variation of degree；DSC is specific heat capacity variation test glass transition temperature from glassy state to elastomeric state transformation using sample.

TMA method and plavini are static method, require Cooling rate slow during the test, and time-consuming for experiment, to sample Size require it is relatively high, sample dosage is bigger, and inflection point is unobvious, and the error of data processing is larger.

DSC method tests solid propellant, since solid propellant sample contains a large amount of solid components, so that than thermal change Measurement becomes difficult, and glass transition inflection point is unobvious.

Summary of the invention

The present invention provides a kind of utilization dynamic thermomechanical instrument compressive deformation mode test HTPB propellant glass transition temperature The method of degree can characterize glass transition temperature with the test propellant dynamic modulus variation of dynamic thermomechanical instrument.

The test method of present invention offer HTPB propellant glass transition temperature, comprising the following steps:

1) sample preparation, using propellant sampling machine by propellant sample according to casting direction prepare slabbing, be then made with Dynamic thermomechanical analysis apparatus with the sample that is consistent of compression grip size；

2) sample is placed in compression clamp middle position, adjusts compression clip by the compression clamp that selection dynamic thermomechanical instrument is equipped with Have push rod, contacts compression clamp with propellant sample surfaces, it is ensured that compression clamp and sample are matched with temperature sensor and other Part is contactless, closes insulated hold；

3) it is tested using dynamic thermomechanical instrument compressive deformation mode, dynamic parameter is set, control heating rate is 2 ~ 2.5 DEG C/min, ess-strain frequency 1Hz, dynamic force is 2.0 ~ 3.0N, and static force is 0.1 ~ 0.5N, and 10 ~ 30 μm of amplitude, sample is surveyed It is positioned below before examination in -120 DEG C of environment temperatures after constant temperature, starts to warm up test；

HTPB propellant glass transition temperature is determined according to the glass transition temperature curve of test.

Further, in step 1), sheet sample with a thickness of 2 ± 0.5mm.

Further, in step 1), last obtained sample is 10 ± 0.5mm of diameter cylindrical body, and the cylindrical body is from sheet Vertical sampling on sample.

Further, the sample that step 1) prepares is placed on 2h in drier and discharges stress.

Further, the compression clamp in step 2 is using preceding by dynamic mass, empty set system, system stiffness and temperature school It is quasi-.

Further, control heating rate is 2.5 DEG C/min, ess-strain frequency 1Hz, dynamic force 2.5N, static force For 0.5N.

Further, constant temperature time is 10min or more in step 3), reaches required environment temperature using liquid nitrogen cooling.

The present invention is a kind of dynamic using dynamic thermomechanical analysis test composite solidpropellant glass transition temperature Method during alternating temperature, applies the stress of the sine wave variation of certain frequency to it, by measurement sample to the corresponding of dynamic force The case where feature, test sample mechanical behavior varies with temperature, multiple relaxations of molecular motion can be obviously distinguished, research is high Polymers mechanical relaxation process.

Dynamic thermomechanical analysis apparatus is furnished with different fixtures, and different fixtures correspond to different deformation mode and inhomogeneity pattern Product, corresponding different deformation mode and size.Mainly there is mono-/bis-cantilever fixture, be suitble to soft to moderate stiffness sample, is mainly used for Thermoplasticity and high damping material；Shearing clamp, for the soft sample with static force, high-damping sample；Stretching clamp, for rigid Property sample；Three-point bending fixture, for rigidity, low resistance sample, such as metal, ceramics, highly filled thermohardening polymer, height is filled out Fill crystallization oriental cherry polymer etc.；Compression clamp is suitble to medium slight sample, is mainly used for the samples such as thermoplasticity, rubber.For The test of HTPB composite propellant glass transition temperature, Domestic Correlative Standard do not use dynamic thermomechanical analysis apparatus Test the introduction of composite solidpropellant glass transition temperature.

Since propellant is a kind of composite material containing energy of binder elastomer and solid component composition, elastic body active will be by Two kinds of groups of binder and plasticizer are grouped as, and according to Fox's equation, two kinds of mixed glass transition temperatures of liquid group are taken Certainly in the mass fraction of both components and their glass transition temperature.Binder is the important component and bullet of propellant Property matrix, it is affected to the processing performance of propellant, mechanical property, glass transition temperature, since fourth hydroxyl glue is poly- Urethane elastomer, in its macromolecular chain, there are butadiene soft segment, chain extender and curing agent reaction generate hard section, and other are matched For square propellant since its binder, plasticiser system are different, soft segment is different from fourth hydroxyl, under certain condition, hard section and soft segment Microphase-separated occurs, macro manifestations are the loss peak on dynamic mechanical, i.e. glass transition temperature, therefore for different binders The propellant of system, physicochemical characteristics and the method for detecting glass transition temperature are distinct.

Sample to be tested is HTPB composite propellant in the present invention, and HTPB propellant is by fourth hydroxyl glue as binder Composite material, fourth hydroxyl characteristic determine propellant characteristic.By being examined to HTPB composite propellant sample physical property, From sample preparation molding effect, Main Components reaction mechanism, sample viscous-elastic behaviour etc. carries out experiment, due to composite solidpropellant Sample has certain viscoplasticity, and shore hardness is 70 ~ 80, and compact model is selected to carry out composite solidpropellant glass transition Temperature test

When testing propellant glass transition temperature using dynamic thermomechanical instrument, test heating rate, ess-strain frequency need to be determined The parameters such as rate, dynamic force, static force.

For heating rate, since the raising of heating rate increases glass transition temperature, although high heating rate is surveyed Glass transition temperature than low heating rate to measure glass transition accurate, but glass transition future can be made by being rapidly heated It obtains and completes, just enter higher temperature, cause temperature lag, and heating rate is faster, the temperature of various pieces in sample It is distributed more uneven, the no representativeness of the measured value of acquisition, low heating rate is small, and " mutation is small " cannot obtain accurate survey Definite value, and the period is long determines that heating rate is (2 ~ 2.5) DEG C/min in the present invention, is the key that test glass transition temperature Condition,.

For ess-strain frequency, influence of the ess-strain frequency to glass transition temperature is identical as heating rate, abides by WLF equation is followed, ess-strain frequency increases, and glass transition temperature also increases, and compressive deformation mode is determined in the present invention Lower ess-strain frequency is 1Hz, and test result figure is stablized, and transformation peaks are obvious.

For dynamic force, static force selection, dynamic force, static force setting are related with sample characteristics of for example, when external dynamic force exists The loss dynamic force for occurring energy when to viscoelastic material load is excessive, when temperature develops from low to high and passes through glass transition When temperature, the high molecular structural form of material internal changes, the variation of viscoplasticity relevant to molecular morphosis therewith, If dynamic force is excessive, sample copy sub-chain motion is destroyed, can not really reflect that dynamic modulus changes in temperature-rise period；Dynamic force mistake It is small, it can not detect that sample modulus, binding test feature of jigs, propellant glass transition temperature dynamic force are set as (2 ~ 3) N, static force are set as (0.1 ~ 0.5) N.

Currently, the test method various engines composite solidpropellant glass transition temperature test in into Application is gone, glass transition temperature is obvious, high sensitivity, and the test of composite solidpropellant glass transition temperature is suitble to want It asks.

Detailed description of the invention

Fig. 1 is product test glass transition temperature curve graph in embodiment 1.

Fig. 2 is product test glass transition temperature curve graph in embodiment 2.

Specific embodiment

Below with reference to embodiment, the present invention is furture elucidated.