[PersistenceModeAttribute(PersistenceMode.InnerProperty)]
public AnimationSettings CollapseAnimation { get; }

<PersistenceModeAttribute(PersistenceMode.InnerProperty)> 
Public ReadOnly Property CollapseAnimation As AnimationSettings
	Get

public:
[PersistenceModeAttribute(PersistenceMode::InnerProperty)]
property AnimationSettings^ CollapseAnimation {
	AnimationSettings^ get ();
}

[<PersistenceModeAttribute(PersistenceMode.InnerProperty)>]
member CollapseAnimation : AnimationSettings with get

Property Value

Use the CollapseAnimation property to customize the collapse animation of the KaxToolBar dropdown items - KaxToolBarDropDown and KaxToolBarSplitButton. You can specify the Type and the Duration of the collapse animation. To disable collapse animation effects you should set the Type to AnimationType.None.
To customize the expand animation you can use the ExpandAnimation property.

ASPX:

<kettic:KaxToolBar ID="KaxToolBar1" runat="server">

<CollapseAnimation Type="OutQuint" Duration="300" />

<Items>

<kettic:KaxToolBarDropDown Text="Insert Html Element" >

<Buttons>

<kettic:KaxToolBarButton Text="Image" />

<kettic:KaxToolBarButton Text="Editable Div element" />

</Buttons>

</kettic:KaxToolBarDropDown>

<kettic:KaxToolBarSplitButton Text="Insert Form Element" >

<Buttons>

<kettic:KaxToolBarButton Text="Button" />

<kettic:KaxToolBarButton Text="TextBox" />

<kettic:KaxToolBarButton Text="TextArea" />

<kettic:KaxToolBarButton Text="CheckBox" />

<kettic:KaxToolBarButton Text="RadioButton" />

</Buttons>

</kettic:KaxToolBarSplitButton>

</Items>

</kettic:KaxToolBar>

void Page_Load(object sender, EventArgs e)
{
    KaxToolBar1.CollapseAnimation.Type = AnimationType.Linear;
    KaxToolBar1.CollapseAnimation.Duration = 300;
}

Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    KaxToolBar1.CollapseAnimation.Type = AnimationType.Linear
    KaxToolBar1.CollapseAnimation.Duration = 300
End Sub

Reference